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Practical Embedded Controllers Design and Troubleshooting with the Motorola 68HC11 IDC Technology Paperback 1st Edition John Park
Practical Embedded Controllers Design and
Troubleshooting with the Motorola 68HC11 IDC
Technology Paperback 1st Edition John Park Digital
Instant Download
Author(s): John Park
ISBN(s): 9781417505692, 1417505699
Edition: 1
File Details: PDF, 18.73 MB
Year: 2003
Language: english
Practical Embedded Controllers Design and Troubleshooting with the Motorola 68HC11 IDC Technology Paperback 1st Edition John Park
Practical Embedded Controllers: Design and
Troubleshooting with the Motorola 68HC11
Titles in the series
Practical Cleanrooms: Technologies and Facilities (David Conway)
Practical Data Acquisition for Instrumentation and Control Systems (John Park,
Steve Mackay)
Practical Data Communications for Instrumentation and Control (Steve Mackay,
Edwin Wright, John Park)
Practical Digital Signal Processing for Engineers and Technicians (Edmund Lai)
Practical Electrical Network Automation and Communication Systems (Cobus
Strauss)
Practical Embedded Controllers (John Park)
Practical Fiber Optics (David Bailey, Edwin Wright)
Practical Industrial Data Networks: Design, Installation and Troubleshooting (Steve
Mackay, Edwin Wright, John Park, Deon Reynders)
Practical Industrial Safety, Risk Assessment and Shutdown Systems for
Instrumentation and Control (Dave Macdonald)
Practical Modern SCADA Protocols: DNP3, 60870.5 and Related Systems (Gordon
Clarke, Deon Reynders)
Practical Radio Engineering and Telemetry for Industry (David Bailey)
Practical SCADA for Industry (David Bailey, Edwin Wright)
Practical TCP/IP and Ethernet Networking (Deon Reynders, Edwin Wright)
Practical Variable Speed Drives and Power Electronics (Malcolm Barnes)
Practical Embedded Controllers:
Design and Troubleshooting with the
Motorolla 68HC11
John Park ASD, IDC Technologies, Perth, Australia
Newnes
An imprint of Elsevier
Linacre House, Jordan Hill, Oxford OX2 8DP
200 Wheeler Road, Burlington, MA 01803
First published 2003
Copyright  2003, IDC Technologies. All rights reserved
No part of this publication may be reproduced in any material form (including
photocopying or storing in any medium by electronic means and whether
or not transiently or incidentally to some other use of this publication) without
the written permission of the copyright holder except in accordance with the
provisions of the Copyright, Designs and Patents Act 1988 or under the terms of
a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road,
London, England W1T 4LP. Applications for the copyright holder's written
permission to reproduce any part of this publication should be addressed
to the publisher
British Library Cataloguing in Publication Data
A catalogue record for this book is available from the British Library
ISBN 07506 58029
Typeset and Edited by Vivek Mehra, Mumbai, India
(vivekmehra@tatanova.com)
Printed and bound in Great Britain
Special thanks to
Industrial Automation
www.cs.jcu.edu.au/~gregory/hc11/
All photos in this book courtesy of
Cursor Magic
www.cursormagic.com
photos@cursormagic.com
For information on all Newnes publications, visit
our website at www.newnespress.com
Contents
Preface xiii
1 Introduction 1
1.1 Microcontroller introduction 1
1.2 Microcontroller design and functions 3
1.3 Assembly language programming 5
1.4 Inputs and outputs 7
1.5 Data communication 8
1.6 Noise reduction 9
1.7 Grounding solutions 10
1.8 Installation techniques 11
1.9 Conclusion 12
2 Microcontroller basics 13
2.1 Introduction 13
2.2 Number systems —binary, hex, and decimal 17
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2.4 Accumulators, A, B and D 22
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2.5 Registers —X, Y, the stack and ports 25
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2.6 Communications synchronous and asynchronous 28
vi Contents
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2.9 Conclusion 37
3 Microcontroller programming 39
3.1 Introduction to programming the microcontroller 39
3.2 Programming structure and specifications 41
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3.3 Addressing modes 49
3.4 Load, stores and transfers 50
3.5 Arithmetic operations 51
3.6 Logical operations 52
3.7 Shifts and rotates 53
3.8 Index registers and the stack 54
3.9 Condition code register 57
3.10 Branches, jumps, interrupts and calls 57
3.11 BASIC and C++ 58
 ('9/) 
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3.12 Conclusion 58
4 Microcontroller memory 60
4.1 Introduction to memory 60
4.2 User RAM 61
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Contents vii
 +^ZKXTGR8'3 
4.3 BUFFALO routines, memory map and vectors 64
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4.4 Interrupts, vectors and pseudo-vectors 66
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4.5 Control registers 70
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4.6 EEPROM 71
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4.7 Conclusion 74
5 Microcontroller inputs and outputs 76
5.1 Introduction to inputs and outputs 76
5.2 Single ended vs differential inputs 77
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5.3 Digital inputs 80
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5.4 Digital outputs 82
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5.5 Analog inputs 84
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5.6 Digital control of analog devices 87
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5.7 Keypad interfacing 88
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viii Contents
5.8 LCD interfacing 91
 2)*YULZ]GXKYKZ[V 
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5.9 Conclusion 95
6 Data communications 96
6.1 Introduction to data communication 96
6.2 Basics of serial data communication 97
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6.3 Open system interconnection model 100
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6.4 Modes of communications 103
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6.5 RS-232 107
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6.6 RS-485 111
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6.7 Fiber optic cables 114
6.8 Fieldbus protocols used in controllers 115
6.9 Conclusion 116
7 Noise reduction 118
7.1 Introduction to noise reduction 118
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Contents ix
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7.3 Capacitive coupled noise 129
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7.4 Magnetically coupled noise 130
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7.5 EMC and noise reduction in PCB design 132
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7.6 Conclusion 136
8 EMC grounding solutions 137
8.1 Introduction to EMC grounding solutions 137
8.2 EMC grounding 138
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8.3 EMC grounding on a PCB 143
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8.4 Protecting a PCB from lightning 150
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8.5 Microcontroller equipment ground 153
8.6 Enclosure or safety ground 154
 9VOQKJKGXZNMXU[TJY 
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8.7 Conclusion 157
x Contents
9 Installation and troubleshooting 159
9.1 Introduction to installation and troubleshooting 159
9.2 Connections —screw, crimp and solder 160
 9IXK]IUTTKIZUXY 
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9.3 Cable runs and trays 166
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 .UXO`UTZGRX[TYGTJZXG_Y 
9.4 Cable ties and mounting 169
9.5 Cooling, heating and air conditioning 170
9.6 Wire management in a cable run 171
9.7 Conduit installation 172
9.8 Troubleshooting techniques 173
9.9 Safety considerations 174
9.10 Conclusion 175
10 End notes 176
10.1 Conclusion 176
10.2 CPU design and functions 176
10.3 Assembly language programming 177
10.4 Memory 178
10.5 Inputs and outputs 178
10.6 Data communication 179
10.7 Noise reduction 180
10.8 Grounding solutions 181
10.9 Installation techniques 181
10.10 Final words 182
Practicals 183
Practical 1: Setting up the 68HC11 emulator board 183
Practical 2: Activating LEDs on the EVM 191
Practical 3: Reading switches on the EVM 197
Practical 4: Sending characters to an LCD display 204
Practical 5: Reading keypad input 212
Contents xi
Practical 6: Using the PAT software 221
Practical 7: Viewing character data transmission 226
Practical 8: Troubleshooting a data communication system 233
Practical 9: Troubleshooting a protocol problem 236
Bibliography 242
Index 243
Preface
From microwave ovens to alarm systems to industrial programmable logic controllers (PLCs) and
distributed control systems (DCSs), embedded controllers are running our world.
Embedded controllers are used in most items of electronic equipment today. They can be thought of
as intelligent electronic devices used to control and monitor devices connected to the real world. This
can be a PLC, DCS or a smart sensor. These devices are used in almost every walk of life today. Most
automobiles, factories and even kitchen appliances have embedded controllers in them.
The microcontrollers that are at the heart of these and many more devices are becoming easier and
simpler to use. But when these devices fail, the solution to the problem needs to be found and repairs
done quickly.
This book will help technicians, engineers and even the casual user understand the workings of
microcontrollers, along with the most common problems and their solutions.
This book covers all aspects of embedded controllers but is biased towards troubleshooting and
design. The book also covers design, specification, programming, installation, configuration and
troubleshooting.
After reading this book we hope you will have learnt how to:
• Design, set up and program a complete embedded controller development system
• Apply the latest techniques in programming these versatile devices
• Apply troubleshooting tips and tricks for microcontrollers
• Apply the best techniques for installation of microcontrollers
• Fix problems due to electrical noise and interference
• Design correctly the first time to avoid grounding and EMC problems
• Choose and configure the correct software
Typical people who will find this book useful include:
• Electronic technicians and engineers
• Instrumentation and control engineers and technicians
• Process control engineers and technicians
• Electrical engineers
• Consulting engineers
• Process development engineers
• Design engineers
• Control systems sales engineers
A basic knowledge of electrical principles is useful in understanding the concepts outlined in the
book, but the contents are of a fundamental nature and are easy to comprehend.
The structure of the book is as follows.
Chapter1 /TZXUJ[IZOUT This chapter gives a brief overview of the main components of a
microcontroller.
Chapter 2  3OIXUIUTZXURRKX HGYOIY. A review of the basics of this device with a
discussion on number systems, Boolean logic, accumulators, registers, data communications, power
systems, crystals and oscillators, is done in this chapter.
xiv Preface
Chapter3 3OIXUIUTZXURRKXVXUMXGSSOTM A review of the simple techniques involved
in programming a microcontroller with a discussion on the various programming issues such as
programming structures, addressing modes, operations and finally a short comparison of C++ and
BASIC, is done in this chapter.
Chapter4 3OIXUIUTZXURRKXSKSUX_ The main types and techniques in the effective use
of memory such as user RAM, BUFFALO routines, interrupts, control registers, and EEPROM are
assessed here.
Chapter5 3OIXUIUTZXURRKX OTV[ZYGTJU[ZV[ZY. Analog and digital inputs, keypad
and LCD interfacing are described here.
Chapter6 *GZGIUSS[TOIGZOUTY This important topic is broken down into a discussion
on the fundamentals, the OSI model, modes of communication and RS-232 and RS-485.
Chapter 7  4UOYK XKJ[IZOUT This chapter gives an overview of noise reduction and a
discussion on conductive, capacitive, and magnetically coupled noise.
Chapter8 +3)MXU[TJOTMYUR[ZOUTY The most important features of grounding (and
protection from lightning) to protect the microcontroller from the effects of EMC are discussed here.
Chapter9 /TYZGRRGZOUTGTJZXU[HRKYNUUZOTM This chapter is a short discussion on
connections, cable runs and trays, wire management and troubleshooting techniques.
Chapter10 +TJTUZKY. A wrap discussion on the issues discussed in the earlier chapters
with a few words on assembly language programming, memory, inputs and outputs, data
communication, noise reduction and grounding solutions and finally installation techniques.
Introduction
Objectives
When you have completed this chapter, you will be able to:
• Describe the basic parts and functions of microcontrollers
• Explain what assembly language is and how it is used
• Describe memory mapping
• Describe the basics of inputs and outputs
• Describe what types of data communications controllers use
• Explain noise reduction and its relationship to good signals
• Describe potential grounding problems
1.1 Microcontroller introduction
Embedded controllers are used in most commercial and industrial electronic equipment.
The sheer volume of embedded controllers used in the world drives us to understand how
they work and then how to troubleshoot and repair them. The microcontrollers and
support chips used in these controllers are becoming smarter and easier to use. This is
bringing the design and use of embedded controllers to more and more engineers hence
the need for a good understanding of what embedded controllers are and how to
troubleshoot them.
Embedded controllers are intelligent electronic devices used to control and monitor
devices connected to the real world. This can be a microwave oven, programmable logic
controller (PLC), distributed control system (DCS) or a smart sensor. These devices are
used in almost every walk of life today. Most automobiles, factories and even kitchen
appliances have embedded controllers in them. As time goes on and electronic devices
get smarter and smaller, the embedded controller will be in or associated with everything
we touch throughout the day.
Early embedded controllers contained a CPU (central processing unit) and a multitude
of support chips. As time went on, support chips were included in the CPU chip until it
became a microcontroller. A microcontroller is defined as a CPU plus random access
memory (RAM), electrically erasable programmable read only memory (EEPROM),
2 Practical Embedded Controllers
inputs/outputs (I/O) and communications (Comms). The embedded controller is a
microcontroller with peripherals such as keypads; displays and relays connected to it and
is often connected to other embedded controllers by way of some type of communication
system.
Figure 1.1
Embedded controller development board
Figure 1.2
Keypad for embedded controller
Electronic equipment is becoming more and more susceptible to noise and other outside
influences that can cause catastrophic problems. To be able to troubleshoot and ultimately
repair the embedded controller it is not only necessary to understand the inter-workings of
the embedded controller but also the external forces that can affect the normal operation
of the controller. This may be noise, bad connections or incorrect installation of the
system. Often simple things like bad grounds or incorrectly made connections can cost
the user hundreds, if not thousands of dollars in down-time. Although the embedded
controller ultimately can be a complicated device, when disassembled into its basic parts
it becomes simple, clear and easy to understand.
Introduction 3
1.2 Microcontroller design and functions
The microcontroller is a direct descendent of the CPU, in fact every microcontroller has a
CPU as the heart of the device. It is therefore important to understand the CPU in order to
ultimately understand the microcontroller and embedded controller.
The central processor unit (CPU) is the brain of the microcontroller. The CPU controls
all functions and uses the program that resides in RAM, EEPROM or EPROM to
function. The program may reside in one or more of these devices at the same time. Part
of the program might be in RAM while another might be in EEPROM.
Figure 1.3
68HC11 CPU
A program is a sequence of instructions that tell the CPU what to do. These instructions
could be compared to instructions a teacher may give to a student to get a desired result.
The instructions sent to the CPU are very, very simple and it usually takes many
instructions to get the CPU to do what is necessary to accomplish a task. Upper level
programming languages like BASIC and C++ include multiple instructions in one
command to speed up the process of programming the CPU. Just like the human brain the
CPU is made up of regions that have specific functions. These components are controlled
by the program instructions.
The main components of the microcontroller are as follows:
• CPU
• External address bus
• External data bus
• External control bus
• Internal RAM
• Internal ROM
• Internal ERPROM
• Internal EEPROM
• Internal registers
• Digital inputs
• Counter inputs
• Digital outputs
• Analog inputs
• Serial data communications
• Parallel ports
4
Practical
Embedded
Controllers
Figure 1.4
Block diagram of a microcontroller
Introduction 5
This may seem like a large number of components, but grasping the complete
microcontroller system becomes very easy once each of the individual components is
understood.
In a microcontroller, the CPU uses an internal parallel address and data bus to
communicate with memory components like RAM, EEPROM and ROM. It also uses this
internal bus to talk to communication systems, I/O ports and registers. The internal
microcontroller memory components such as RAM, ROM, EPROM and EEPROMs are
used to store (either temporary or permanently) data and program instructions. The
internal registers are used to manage temporary bytes of data, like addressing for the
program. The serial communications section lets the microcontroller communicate with
other devices via a communication standard such as RS-232 or RS-485. The parallel ports
such as A, B, C, D and E can be used to transfer data to and from external memory chips
or devices. These ports can be used to read and write to devices like keyboards and
LCDs. An external parallel data bus can also be used by the microcontroller to activate or
read external devices like switches, relays, and LEDs. The digital I/O and analog inputs
are used to bring inputs and outputs to and from the microcontroller.
1.3 Assembly language programming
Often when assembly language programming is mentioned programmers groan that it is
all too hard and difficult. Assembly programming is actually easy and simple (almost too
easy). The two best things about assembly language programming is the control it gives
the programmer over the microcontroller and the minimal instructions needed to do the
job. Using BASIC or C++ is compared by some to using a chain saw to peel an egg. From
a functional point of view, using BASIC, C++ or some other high-level language is
simple and straightforward but it does use a huge amount of memory compared to
assembly language. This limits the size of the program that the programmer can load into
the microcontroller. Chip manufactures have gone to great lengths to include RAM, ROM
and EEPROM on board the microcontroller. This memory is usually only hundreds of
bytes. Programming the microcontroller without using external memory chips is almost
impossible using BASIC or some other high level languages. Therefore, assembly
language becomes the only option.
Programming is often compared to painting a picture. One difference though is that in
art it is often unclear when the painting is finished. In programming the program is done
when it does what it was designed to do. This can be defined and specified before the
program is written. Strangely enough, this step of exacting specification is often
overlooked and the program is just let to evolve. As in most endeavors, preparation is
everything. The participants in the programming process should spend a large amount of
time preparing for the writing of the program.
In its simplest form, the program is a sequential set or list of instructions that tell the
microcontroller what to do. Each step in the process is done in a specific order. The
process is divided up into separate individual sections called subroutines. A subroutine is
a small program that performs some tiny function within the overall program. An
example of this could be starting a car. The sequence of events that are used to start a car
could be called a subroutine within the overall program of driving the car. It is a very
specific and defined sequence of acts or instructions. It is stand-alone and can be repeated
when necessary. In programming language, it would go something like...
6 Practical Embedded Controllers
Figure 1.5
Starting the car
Jump to ‘Start the Car’
Start the Car Put key in ignition
Started Turn key clockwise to the start position
Has the car started?
If the car has started, release the key and go to ‘End’
If not, continue to hold the key in the start position
Loop to ‘Started’
End Return to main program (i.e. drive the car)
Put Key in
Ignition
TurnClockwise
Drive the Car
Start the Car
Has T he Car
Started?
No
Yes
Figure 1.6
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companies crossing the Intombe River, 5 miles from Luneberg, had
camped at the station when the water rose, and the 5th Company
was unable to cross. A raft was employed, and one-third of the
company had reached the west side of the stream of the river at
nightfall. Half an hour before daylight next day an attack was made
by Umbeline, assisted by Manyoba’s
174
tribe. Nearly every one on
the east bank of the river was assegaied, many in their tents, and
the Zulus, taking to the water like otter hounds, crossed and
endeavoured to overwhelm the 34 men on the Western bank. Some
10 of these, however, were not only skilfully but courageously
handled by Sergeant Booth, who successfully brought the party
back. In all 40 of our men were killed.
I went over at daylight to the scene—40 miles distant—to inquire
into the disaster, and to ensure our system for security being
adopted for the future, returning in the afternoon to camp, as I had
arranged a long ride for next day.
Uhamu, a brother of Cetewayo’s, came into our camp
175
in the
Cape cart which I sent for him, he being so enormously bulky that it
was difficult to find a horse to carry him. He had made many
appointments, but in the procrastinating Zulu fashion had failed for
various reasons to keep them, until Colonel Buller had ceased to
believe in his being willing to come over to us. Finally he went to my
Assistant Political Agent, Norman Macleod, in Swaziland. He was no
sooner in our camp than he asked me if I would be good enough to
go after his wives. “How many are there, Uhamu?” “I don’t know but
about 300,” he replied vaguely. “But you have got two now with
you,” I urged. “These are only slaves,—I should like to have the
others.” “I am not willing to take the responsibility of escorting all
your wives unless you will come with me.” “Oh, in such a case, Great
Commander, I would sooner do without them.”
Uhamu’s head Place was in a rugged country, 45 miles from our
camp, between the Black Umvolosi and Mkusi Rivers, and Ulundi
being within 40 miles of the kraal, there was the possibility of our
return being cut off if either of Uhamu’s men let it be known, by
Cetewayo’s adherents, they were collecting the women in
anticipation of our arrival.
Looking, however, to the Political effect of getting out the tribe, I
decided to go down, and on the 14th March started with 360
mounted men under Buller, and 200 of Uhamu’s men, many of
whom had fought against No. 3 Column at Isandwhlana. Some of
my officers objected to my leaving Buller and the White men and
accompanying Uhamu’s people, by a short cut over the Zunguin
Mountain, which would save three hours’ travelling. I argued that
there was absolutely no danger while their Chief was located in my
camp, especially as the men looked forward to bringing their wives
and children back with them.
I took with me Captain Woodgate,
176
Mr. Llewellyn Lloyd,
177
my
interpreter, Lieutenants Bigge,
178
Bright,
177
and Lysons.
179
We joined
Colonel Buller under the Inhlobane, down the slopes of which some
aggressive Zulus came, and fired at us at long ranges. I allowed two
or three men to return the fire, and then had two shots myself, and
the bullets falling amongst the Makulusi—for they occupied the
mountain, silenced their fire.
About 2 p.m. we saw a few cattle to the south of us, and Piet
Uys despatched his two boys, aged fifteen and thirteen, with half a
dozen men to drive them to us. Master Dirks Uys shot a Zulu. When
the father heard the firing he tried to look unconcerned, and was too
proud to ask me (for his eyes were not as good as mine) if I could
see what the lad was doing. Lysons told me later that he kept on
repeating, “Are they coming back yet?” The men brought back about
100 head of cattle, and I said to my friend Piet, “I am glad the lad
has come back. I saw that you were nervous.” “Yes,” he said, “I am
always nervous if I am not there myself,” a feeling which I
understood. Nevertheless he risked them in every skirmish, though
the warmth of his affection for his youngest born—Piet was a
widower—was evident. In an argument he said something which I
thought unworthy of the bigness of his character, and I remarked,
“Why, you risk Dirks for us, you should not talk of farms and
property”; and he replied, his eyes filling, “You are quite right, I
would not give Dirks for all Zululand!” An hour or two later Piet
called out that he saw Zulus, and galloped off with his two boys, but
on this occasion nothing happened, for the Zulus he had sighted
were some of Uhamu’s men, who, taking advantage of our presence,
were coming to join us.
We marched steadily till sunset, when we off-saddled for an
hour, to let the horses graze, and, moving off again at dusk, at 9.30
p.m. reached the spot I had arranged with Uhamu, having taken
three hours to pass over the last seven miles. We descended a
mountain by a goat path, and all the Europeans dismounted; but I,
being tired from having been touched by the sun in the forenoon,
threw the reins on my pony’s neck and let him choose, or rather
feel, the path,—it was too dark to see, and we got down without
accident.
At sunset Uhamu’s 200 men who accompanied me had asked me
to stop, declaring they were tired. This I refused, and when we got
down they had nearly cooked their food, having passed down by a
still steeper but shorter path. Before I went to sleep I had some of
the women, for whom I came brought out of a cave three miles off,
as I foresaw there would be delay next morning, and every hour
added to the chance of our being caught by some of Cetewayo’s
regiments. During the night I sent 6 miles away to some caves
where I heard there were more women, being unable to sleep
soundly, although greatly fatigued, for one troop of the Frontier Light
Horse, linked
180
in line, nearly walked over me, after they had eaten
all the grass within reach. Buller came and pulled them away;
indeed, every time I awoke in the night I saw him walking up and
down, for he felt we were in a precarious position.
At daylight we shook ourselves, and began to start—a long
stream of humanity. The Refugees numbered between 900 and
1000, men, women, and children. Many of the latter, although only
five years old, walked from 6.30 a.m. till 9.30 p.m., when they had
covered 30 miles. I sent Captain Barton on in front, while Colonel
Buller and I remained behind. At 8.30 we were assured by Messrs.
Calverley and Rorke—two traders who had often been in the district
—that we had got the whole of the women and children. My
engagement was that I would remain till daylight,—that is, six
o’clock. At 8.30 Colonel Buller marched, a small Rear guard,
remaining with me till 10.30, as even then stragglers were coming
in, the last few being shot at, and two assegaied in our sight but too
far off for us to save them. My friend Buller had stoutly declared that
he would have nothing to do with the verminous children,
nevertheless during the march I more than once saw him with six
little black bodies in front of and behind his saddle, children under
five years of age.
As we passed under the Inhlobane, the Makulusi tribe, which
had been reinforced by one of Cetewayo’s regiments from Ulundi,
fired a few shots at us without any effect, and we bivouaced at
nightfall on a small effluent of the White Umvolosi, where Vryheid
now stands.
Next morning I started the procession at daylight, remaining
myself on the top of the Zungu in range to see the Rear guard into
camp. I had sent in for all mule waggons available, to save the
children a farther walk of 10 miles, and was waiting at the top of the
pass, up which we had climbed on the 22nd January, for a dozen
women who were loitering half up the mountain. It was past noon
when I desired Piet Uys to descend and hurry them up, holding his
horse for him, for it was too steep to ride down. When he returned
he said, in his curious mixture of Dutch, German, and English,
“Kurnall, die vrow sie sagt now too sick, presently have baby, then
come quick.” “Piet,” I exclaimed, “oughtn’t we to send some of these
women back to see after her?” “Not necessary, Kurnall, she come.”
Calling Mr. Llewellyn Lloyd, my interpreter, I apprised him of the
situation, and said, “You are not to go into camp until that woman
gets there.” Finally, waiting for the waggons longer than I expected,
I did not reach camp till 5 p.m., and, having had nothing to eat or
drink since our morning cocoa at daylight, I was annoyed to see
Lloyd sitting in his tent with a cup of tea, and observed in a
somewhat irritable tone, “I thought I told you not to come into camp
until the woman who was about to bring a baby into the world had
arrived. “Yes, quite so,” he replied, “but she has been in camp a long
time. Half an hour after you told me, she passed me like one of
Waukenphast’s pictures, doing five miles an hour easily, and I,
suspecting that she had left her baby in the rocks, made her angry
by insisting on seeing it, but she had it right enough under her arm.”
Throughout the weeks of waiting for reinforcements I had
frequent letters of encouragement from the High Commissioner and
Lord Chelmsford; the latter writing to me frankly, said I had caused
irritation amongst the local Civil authorities by the insistent tone of
my communications. I have no doubt that this was accurate, but on
the other hand many were supine, some actually obstructive. I was
unable to induce the Field Cornet of Wesselstroom to take any
effectual steps to send back 400 men who had deserted, out of the
600 enlisted when we crossed the border.
The Transvaal Boers rejoiced in our misfortune, and openly
stated that they intended to rise; some of the Natal authorities
objected to my sending any Refugees into the Colony, advancing the
most absurd reasons. The Political Agent, sent from Pretoria to
Utrecht to assist me, instead of doing so wrote at length that he was
advised that the action of the Administrator of the Transvaal, in
putting the Commando law in force for the Kafirs, was illegal. The
Civil authorities on the Natal and Transvaal border clamoured for
protection, and urged me, but in vain, to fall back to ensure the
protection of certain villages.
The Utrecht Landdrost begged me to encamp close to that
village, while the Landdrost of Wesselstroom, the chief village of the
Wakkerstroom district, spent much time in endeavouring to persuade
me to encamp in front of his village. When I intimated that I was not
interested in Utrecht, as I had ample supplies at Balte Spruit, they
expressed anxiety for the safety of that depot, and importuned Lord
Chelmsford on the subject, who referred the correspondence to me,
and to whom on the 3rd March I wrote in reply: “I have often
considered your proposition about the Zulus masking this position,
and going on to attack Balte Spruit and Utrecht. I do not believe
they are equal to such a manœuvre, and are incapable of remaining
in presence of a Force without attacking it or running away. If all our
mounted men were absent I should feel anxious, but so long as they
are here I could always make the Zulus attack us by sending the
mounted men to follow them if they marched to Balte Spruit. I doubt
Cetewayo turning out more than 30,000 men; if he does, he would
do better to send 20,000 here and 10,000 against you. Moreover,
the moral effect of our being in Zululand is considerable, both on the
Swazis and the Boers.” I discussed fully in this letter a scheme I had
long considered about attacking the Inhlobane, but when Colonel
Buller burnt the Makulusi Kraals, bringing away 500 of their cattle,
the necessity was less apparent, and I did not recur to the plan until
asked to take pressure off the Force relieving Ekowe.
The Civil authorities were not, however, the only demoralised
people. The General, in deference to the apprehensions of the
inhabitants, sent a garrison to hold a village 30 miles behind our
camp, and the Commanding officer marched round by Newcastle,
adding 12 miles to his journey to avoid crossing a bit of Zululand 10
miles on the safe side of Kambula, and on arrival pitched his men’s
tents inside the cattle laager, which was several feet deep in
manure; he became sick in a few days and went away. The next
senior officer, on hearing of the disaster to the Company of the 80th,
on the Intombe 45 miles distant, recalled a Company which was 10
miles behind our camp, at Kambula, for fear of its being surprised,
although there were still four companies 80th Regiment at Luneberg,
and another company from our camp, coal digging, all between him
and the enemy. Indeed, the overweening confidence felt by many
before the war had now changed into unreasoning apprehension.
The one great heroic figure throughout the time when men’s
minds were depressed was undoubtedly the High Commissioner, Sir
Bartle Frere. He spent many days and nights in supporting all my
demands, and in coercing unwilling and timorous Civil subordinates.
With great address and moral courage he prevented an outbreak of
the Boers, projected after the destruction of No. 3 Column.
On the 12th March I took the opportunity, when acknowledging
the thanks by the High Commissioner and the General, to point out
how much I owed to the Staff officers, Mr. Llewellyn Lloyd, my
interpreter and Assistant Political Agent, Captain Ronald Campbell of
the Coldstream Guards, Captain Vaughan, R.A., Director of
Transport, and Mr. Hughes, Assistant Commissary-General, who
worked literally day and night to carry out my wishes.
The difficulties of transport for the increased force, which was
coming out to reinforce Lord Chelmsford’s command, being always
before me, I wrote urging that we should purchase sufficient at
once, as hiring was not only extravagant but impracticable. The
Chief replied on the 14th March that he had handed my offer to
provide waggons to the Commissary-General, and was surprised that
he did not jump at the offer, but added, “I do not like to interfere
with his arrangements; please do as you like best yourself. I
congratulate you on the surrender of Uhamu, the entire credit of
which belongs to you. You can do anything you like with your
column; if you like to attack the Inhlobane, pray do so.”
I had previously asked permission to send officers to the Free
State to purchase mule transport, foreseeing that the final advance
on Ulundi might be delayed until the grass on the veldt would no
longer suffice for oxen, and thus render the movement impossible
without mule transport. After writing in vain repeated reminders for
five weeks, I decided to act on the qualified sanction of my Chief in
his letter of the 14th, “Please do as you like best yourself”; and on
the 23rd sent two officers to the Free State, giving the senior,
Captain Bradshaw, 13th Light Infantry, a cheque for £56,000, drawn
on the Standard Bank of South Africa. They did very well indeed,
enabling me to supply the 2nd Division, without which, as Lord
Chelmsford wrote later, the advance would have been impossible.
The only comment made by the War Office on my action was to
the effect that, as the money could not be all expended at once, I
ought to have drawn two cheques, each for £28,000 at different
dates, as I should thus have saved the amount of interest
unnecessarily paid to the Bank. In my reply, while admitting my
mistake, I remarked I had already spent for the Government over
£50,000 without the assistance of a Paymaster, and it was therefore
reasonable to debit the salary of such an officer against the amount
of interest I had unnecessarily incurred.
The day Captain Bradshaw left was one of some anxiety. I had
arranged a raid, by all the mounted men, in a North-Easterly
direction to the Southward of Luneberg, to destroy the crops of one
of our most troublesome foes. A convoy of 40 waggons was going in
the opposite direction, South-South West to Balte Spruit, escorted by
Infantry, and there was a working party, with an Infantry escort,
employed in removing Potter’s Store, which I had purchased and
was moving from the Pemvane River to Balte Spruit. When we stood
to our arms an hour before daylight the fog was so thick that we
could not see 40 yards, and it did not clear off till the forenoon. I
decided, however, to let the movement proceed as ordered,
preferring the risk of surprise while I was present, to any which
might occur in my absence.
Next morning, when I saw the convoys safe back in camp, I
started and, overtaking Colonel Buller’s 300 men, and 500 of Wood’s
Irregulars, reached Luneberg at sunset on the 24th. Next day we
spread out over the basin of the Intombe River, cultivated by
Umbiline’s tribe, who were Zulus, although he was a renegade
Swazi. We destroyed all the crops we could, and after two long days’
work returned, on the evening of the 26th, to Kambula Hill.
In a letter dated the 19th Lord Chelmsford called my attention to
a paragraph in a Maritzburg newspaper, from a Correspondent with
No. 4 Column, alleging that I was fretting at the inaction imposed on
me by the General, and wrote, “You can undertake any operations
you like, and I shall hear of it with pleasure. I hear all Cetewayo’s
army will be concentrated about Ekowe in a few days, so we shall
have a hottish encounter.” I replied on the 27th, “I do not often see
the letters of the Correspondent, and hold no communication with
him. If I did I should certainly tell him I am perfectly unfettered,
your only action being to support me in every way. Buller has
started, and at 3 p.m. I follow, to try to get up the Inhlobane at
daylight to-morrow. I am not very sanguine of success. We do not
know how steep the Eastern end may be, but I think we ought to
make a stir here, to divert attention from you, although, as you see
by our last reports, it is asserted that you have only Coast tribes
against you, and that all Cetewayo’s people are coming here.”
In the forenoon of the 27th March, the two columns which were
to attack the Inhlobane at daylight next morning marched; I
followed in the evening, intending to lie down 5 miles under the
Western edge of the Inhlobane. The more important part of the
operation was intrusted to Colonel Buller, under whose orders I
placed the two battalions of Wood’s regiment. The 1st battalion,
under Major Leet, bivouacing near the White Umvolosi, where
Vryheid now stands, was intended to ascend the Western end of the
mountain; both columns were to get as high up as they could before
daylight on the 28th. In the orders I stated that, as Cetewayo was
said to be advancing with his whole army, scouts were to be sent to
the South and South-West, to watch the avenues of approach from
Ulundi.
I took with me Mr. Lloyd, Assistant Political Agent and
Interpreter, Captain the Honourable Ronald Campbell, Coldstream
Guards, and Lieutenant Lysons, 90th Light Infantry, Orderly officer,
my personal escort, eight mounted men of the battalion, and seven
mounted Zulus under Umtonga, a half-brother of Cetewayo’s, whom
the father, Umpande, had originally designated to succeed him.
Before I went to sleep I had a long talk with Piet Uys, who was to
accompany Colonel Buller, and had stayed behind to see me, while
the Colonel had bivouacked 5 miles farther to the east. Mr. Potter, a
Captain in the 1st Battalion, Wood’s Irregulars, also came to me.
Both men knew the Inhlobane, and Potter had often been up on it. I
asked whether, if we should have the bad luck after taking the
mountain to see Cetewayo’s army advancing, we could get down on
the North side, and Mr. Potter assured me that we could,—by leading
our horses. Piet Uys was confident that Colonel Buller would get up,
without serious loss, and we agreed that, except in the probable
contingency of the Zulu main army coming in sight, our operation
ought to be a success; then Piet turning to me, said, “Kurnall, if you
are killed I will take care of your children, and if I am killed you do
the same for mine.” We had heard, indeed, for several days that
Kambula was to be attacked, but were informed that the Zulu Army
could not leave till the 27th, as there had been a delay in “doctoring”
one of the largest regiments. This was inaccurate. It had started on
the 25th March.
A
CHAPTER XXX
1879—THE INHLOBANE, 28TH MARCH
The ride to Death—Buller surmounts the mountain—
Fate of two heroic Coldstream Officers—Campbell
and Barton—Major Leet, V.C.—Chicheeli’s description
of Barton’s death—Buller’s heroism—Ronald
Campbell as tender hearted as he was brave.
T 3 a.m. on the 28th I rode Eastward, with the Staff officers and
escort. Captain Campbell and I were silent, but the two
younger men chattered till I wondered whether their voices could
reach the Zulus on the Inhlobane. When Ronald Campbell spoke on
Lloyd’s challenge for his thoughts, he replied, “I am hoping my wife
is well and happy.” Lloyd and Lysons, jubilant at the prospect of a
fight, remarking on my silence, asked, “Are you doubtful, sir, of our
getting up to the top of the mountain?” “Oh no, we shall get up.”
“Then, of what are you thinking?” “Well, which of you will be writing
to my wife to-night, or about which of you young men I shall be
writing to parents or wife?”
Colonel Buller, to avoid risk of being surprised, had shifted
bivouac twice during the night, but at daylight we struck his track
and followed it. We met a Squadron of his Force coming Westwards,
the Commandant having lost his way the previous night, and I
directed him to move to the sound of the firing, which was now
audible on the North-East face of the mountain, where we could just
discern the rear of Colonel Buller’s column mounting the summit. I
followed the Squadron, but when it came under fire, as it did not
advance rapidly, I passed to the front, the track at first being easy to
follow, from worn grass and dead horses of Colonel Buller’s
command lying on it. Hard rock now replaced the beaten down
grass, and as we came under fire I unconsciously, by leading directly
towards the rocks whence the bullets came, missed the easier
gradient, up which Buller’s men had ridden, losing only one officer.
The ground was now steep and very rugged, so we dismounted and
put the horses of my White and Black escort in a cattle kraal, the
walls of which were 2½ feet high. Campbell invited me to leave my
horse. I said, “No; I am a bad walker,” and pulled it after me, Mr.
Lloyd being close on my left hand. Half a dozen of the foremost of
the Irregulars had dismounted sooner, and followed me until Lloyd
and I were within 100 feet of the crest of the mountain, and we
came under well-directed fire in our front, and from both flanks, the
enemy being concealed behind huge boulders of rock.
The men of the Squadron 200 yards behind us now opened fire,
and Mr. Lloyd said, “I am glad of that, for it will make the Zulus
shoot badly.” He had scarcely spoken these words when a Zulu rose
up from behind a rock 50 yards above us, and, touching Lloyd with
my elbow, I observed, “He won’t hit us in the face,” for he laid his
gun directly at my waistbelt. He fired, and Lloyd fell back,
exclaiming, “I am hit!” “Badly?” “Yes, very badly; my back’s broken!”
I tried to lift him on my shoulders, but he was taller than I, and the
ground being steep I stumbled, when Captain Campbell climbing up
said, “Let me lift him,” and carried him on his shoulder 50 yards
down to where the horses were standing in the cattle kraal, under
the walls of which the escort were sheltering. I climbed a few yards
higher, when a Zulu fired at me from underneath a rock, 20 yards
distant. The charge struck my horse immediately in front of the
girth, killing it instantaneously, and as it fell, striking my shoulder
with its head, knocked me down. I heard an exclamation from my
comrades, and scrambling up called, “No, I am not hit!” and as they
began climbing the hill, added, “Please stop where you are. I am
coming down, for it’s too steep to get on any farther, in this place.”
When I got down to the kraal, I saw Mr. Lloyd was dying. He could
no longer speak; obtaining some brandy from Lysons, I tried to pour
a little down his throat, but his teeth were already set.
I told Captain Campbell to order the Irregular horsemen, who
were taking cover under rocks below us, to clear the caves from
whence the firing had come which killed my horse. He found much
difficulty in inducing the men to advance, as they alleged the
position was unassailable; and eventually, leading four of my
personal escort, with Lieutenant Lysons, he climbed up, Bugler
Walkinshaw going with him. I called Walkinshaw back before he was
out of sight, for I wanted help for Mr. Lloyd; and thus he, one of the
bravest men in the Army, missed the chance of gaining the Victoria
Cross. In a few moments one of the men told me that the cave was
cleared, but that Ronald Campbell was dead. He had led the small
party of three or four men, passing up a narrow passage only 2 feet
wide between rocks 12 feet high for several yards, and was looking
down into the cave, when a Zulu fired, almost touching him, and he
fell dead. Lieutenant Lysons and Private Fowler,
181
90th Light
Infantry, undauntedly passing over the body, fired into the cave, and
the few Zulus in it disappeared through another opening.
By the time the men brought Ronald Campbell’s body down, Mr.
Lloyd was dead. Telling Walkinshaw to put his ear down to his heart,
he made sure, and then I tried to put the bodies up on my baggage
animal. The fire from the rocks on all sides was fairly accurate, killing
many out of the 21 ponies we had with us. As bullets were striking
all round me on the stones, my pony moved every time I got
Campbell’s body on my shoulder. Walkinshaw, who was entirely
unconcerned at the bullets, said, “If you will hold it, sir, I will put the
bodies up”; and this he did.
It then occurred to me that in the wallets of the saddle under my
horse, which was lying with all four feet in the air, was Campbell’s
wife’s Prayer book, a small one I had borrowed before starting from
Kambula, as my own was a large Church Service, and I said to
Walkinshaw, “Climb up the hill, and get the prayer book in my
wallets; while I do not want you to get shot for the saddle, you are
to take all risks for the sake of the prayer book.” He climbed up in a
leisurely fashion, and, pulling the saddle from underneath the horse
brought it safely down on his head. We then moved down the
mountain 300 yards, to find a spot on soil clear of rocks.
INHLOBANE, 28th MARCH, 1879
COLONEL EVELYN WOOD TO LORD CHELMSFORD. “MR. LLOYD FELL MORTALLY
WOUNDED AT MY SIDE—CAPTAIN CAMPBELL LEADING IN THE MOST GALLANT AND
DETERMINED MANNER WAS SHOT DEAD. WE BROUGHT THEIR BODIES HALF-WAY
DOWN THE HILL, WHERE WE BURIED THEM, STILL UNDER FIRE”
The operation of digging a grave was laborious, as our only
implements were the assegais of the native escort, and when it had
been completed to about 4 feet in depth, the men got flurried by the
approach of some 300 Zulus from the Ityenteka Nek, and, lifting the
bodies, placed them in the grave. It was not long enough, and
although I realised the possibility of our having trouble with the
approaching Zulus, yet as they were still 600 yards off and were
most of them bad shots at that range, I had the bodies lifted out,
and the grave made a proper length to receive them without the
lower limbs being doubled up. When I was satisfied, I read an
abridged form of the Burial Service from Mrs. Campbell’s prayer
book. We were now assisted by the fire of some of Colonel Buller’s
men, who, seeing our difficulty, opened on the advancing Zulus, and,
being above them, checked their approach. The officer commanding
the Irregulars asked permission to move down the hill to regain
Colonel Buller’s track, and by it he finally reached the summit
without further casualties. He had lost only 6 men dead, and 7
wounded, up to this hour.
As all firing on top of the mountain had now ceased, I decided to
move back, and see how the other column had fared. Passing one of
the Irregulars who had been shot in the thigh, I put him up on one
of the dead men’s horses, and as there was no apparent hurry,
Umtonga’s men drove with us a flock of sheep and goats. We
stopped occasionally to give the wounded man stimulants, being
unconscious that the main Zulu Army was moving on our left,
across, and towards our path. When we were under the centre of
the mountain, Umtonga, whom I had sent out to a ridge on our
danger flank, gesticulated excitedly, explaining by signs that there
was a large army near us. Cantering up, I had a good view of the
Force, which was marching in 5 columns, with the flanks advanced,
and a dense Centre—the normal Zulu attack formation.
I sent Lieutenant Lysons to the officer commanding the western
party with the following order:—
“Below the Inhlobane. 10.30 a.m. 28/3/79.
“There is a large army coming this way from the South.
Get into position on the Zunguin Nek.
E. W.”
The plateau which Colonel Buller’s force had cleared was 150
feet higher than the Lower Plateau on which the western column
stood, but both parties saw the Zulu Army a considerable time
before I did, as I was 1000 feet below them. Buller had seen it at 9
a.m., and the western force had seen it rather earlier, Buller being
engaged in covering a party of 25 of the Frontier Light Horse under
Captain Barton, Coldstream Guards, who were descending the
eastern slope to bury one or two men killed in the assault. Sending
word to Captain Barton to retire, Buller fell back to the western end
of the mountain, and forming some selected men into a rear guard,
he took them down the almost precipitous edge of the Upper
Plateau. The path was down the apex of a salient angle, with long
sides, and the head of the descent was well suited for defence.
Buller’s men had previously collected a great number of cattle, which
had been driven down towards the Zunguin Nek at 7 a.m. Colonel
Buller and all his party would have got safely away had not the
Makulusi, and the men of the Regular regiment with it, taking
courage at the advance of the Zulu Army, emerged from their caves
and harassed the retreat, during which some valuable lives were
lost. Colonel Buller came down, practically the last man, and was at
the foot of the descent from the Upper Plateau, when, seeing men
nearly surrounded by Zulus, he went back on two occasions, and
brought out in succession two on his horse. Piet Uys came down
with him, until he saw one of his sons having difficulty with his
horse, and, going back, was assegaied by a Zulu crouching behind
him.
182
About 80 of the First Battalion of Wood’s Irregulars were
overtaken and killed, and with them, to my great regret, Captain
Potter, and Lieutenant Williams
183
of the 58th regiment.
The main Zulu Army being exhausted by their march, halted
near where Vryheid now stands, but some of their mounted men
came on, and a few of the more active and younger footmen. Before
leaving camp I had given orders for a barricade of planks, 5 feet
high, to be erected, and securely bolted into the ground with
supporting struts, to run between the redoubt and the south end of
the cattle laager, to stop a rush from the ravine on to the fort. To
those who objected that the Zulus would charge and knock it down
by the weight of their bodies, I replied it would cause a delay of
several minutes, during which 300 or 400 rifles, at 250 yards range,
ought to make an additional barricade of human bodies, and I now
sent an order to the Senior officer in camp, to chain up the
waggons, and to continue the strengthening of the barricade. I
wrote I had seen between 20,000 and 25,000 Zulus, and remained
on the Zunguin Mountain till 7 p.m., hoping to cover the retreat of
any more of our men who might come up, being particularly anxious
about Captain Barton,
184
of whom we had had no news since he
descended the eastern end of the mountain.
I never knew until that day the depth of regard which Buller felt
for me. I was sitting on the summit of the Zunguin range when he
climbed up it, and, seeing me suddenly, uttered so fervent a “Thank
God!” that I asked for what he was thankful, and he explained that
he thought I had been cut off at the eastern end of the mountain. It
rained heavily on the evening of the 28th. All the mounted men had
been on the move day and night since the 23rd, when we went to
Luneberg; but at 9 p.m., when a straggler came in to say that there
were some Europeans coming back by Potter’s Store, Redvers Buller
immediately saddled up, and, taking out led horses, brought in 7
men, who were, as we believed, the sole survivors of the parties at
the east end of the mountain.
So far as I know, the only officer who got down the western end
of the Inhlobane on horseback was Major Leet, who commanded the
1st battalion Wood’s Irregulars. Six weeks earlier, at the Athletic
Sports, we had a Tug-of-war between the officers of the 13th and
90th Light Infantry, captained by Leet and myself, and as the 90th
pulled over the 13th Leet wrenched his knee out of joint, and I had
told him to remain in camp on the 27th. This, however, he did not
do, and as he could only hobble, he tried, and successfully, to ride
down the mountain. I believe he got down before the counter
attack; but while on the Lower Plateau, and being followed up
closely by the enemy, he showed distinguished courage in going
back to help a dismounted officer, for which he received the Victoria
Cross.
On the night of the 28th March, as I sat at dinner, I could not
keep my mind off Ronald Campbell, who had sat opposite me for
three months, and had anticipated every want with the utmost
devotion, and I cannot write now, even after the lapse of a quarter
of a century, without pain of the loss the army sustained when my
friend fell. As I visited the outposts at least twice every night from
the date of Isandwhana till after Ulandi, 4th July, my clothes were
nearly always damp from walking through the long grass, which,
when not wet from the heavy rain which fell constantly through the
months of February and March, was soaked with dew, and I had
forbidden either of the Staff accompanying me, because, as we slept
in our boots and clothes, anyone who walked round the sentries got
saturated up to the waistbelt. I had, however, once or twice
suspected that I was being followed, and one night, turning
suddenly in the darkness, I knocked against a man, and then
recognised Campbell’s voice, as he answered my challenge. I said
sharply, “Why are you disobeying orders? What are you doing here?”
“I have always the fear, sir,” he replied, “that one night you won’t
hear the challenge of one of the sentries, and you will be shot.” On
two occasions on which I was in bed with fever for three days, he
nursed me as tenderly as could a woman, and I never saw anyone
play a more heroic part than he did on the morning of the 28th
March 1879.
INHLOBANE MOUNTAIN
—attacked 28th. March 1879.—
Practical Embedded Controllers Design and Troubleshooting with the Motorola 68HC11 IDC Technology Paperback 1st Edition John Park
I
CHAPTER XXXI
1879—KAMBULA, 29TH MARCH
Mist delays the advance of 23,000 Zulus—Piet Uys
having fallen, Burghers leave us—The position under
the Ngaba-ka-Hawane—Bigge—Nicholson—Slade—
Buller teases Zulu Right Wing into a premature
attack—I shoot three Zulu leaders in five successive
shots—Hackett’s Counter attack—His wound—His
character—Death of Arthur Bright—I recommend
Buller for the Victoria Cross.
WENT round the sentries twice during the night, although I did
not anticipate an attack until daylight, feeling sure the large
masses of Zulus I had seen could not make a combined movement
in the dark. When the night was past, the mist was so thick that we
could not see more than a hundred yards. Captain Maude, who had
temporarily replaced Ronald Campbell, asked me if the wood-cutting
party of two companies was to go out as usual. Our practice was
that they should not start till the front was reported clear for 10
miles, but until the sun came out there was no chance of the mist
clearing off, and after thinking over the matter I decided the party
should go, because we had never been able to get up reserve of
fuel, and it was possible the Zulus might not attack that day. Our
men would certainly fight better in two or three days’ time if they
had cooked food, and so I accepted the risk, but ordered two
subalterns to keep ponies saddled to recall the companies in good
time. Fortunately, though 5 miles away, the place was behind the
camp.
All the mounted men had been continuously in the saddle since
daylight on the 23rd, and it was difficult to get a trot out of the
horses;
188
but Commandant Raaf went out with 20 men to the edge
of the Zunguin plateau, and when the mist lifted, about 10 a.m.,
reported the Zulu Army was cooking on the Umvolosi and a tributary
stream.
189
He remained out himself to warn me when they
advanced.
All our arrangements in camp were perfected, with the exception
of the barricade, to which we had added some strengthening pieces.
The Dutchmen came to see me early in the day, to say that, as
Piet Uys was dead they wished to go home, and, except half a dozen
who had hired waggons to us, they departed. Great pressure had
been brought on my gallant friend Piet to induce him to withdraw
from the column. His friends told him he was a traitor to their cause,
but Uys always replied that although he disliked our policy, he
thought it was the duty of a White man to stand up with those who
were fighting the Zulus.
190
Between 80 and 100 of Uhamu’s men, who held on to the cattle
they had driven from the Inhlobane, were overtaken and killed near
the Zunguin Mountain on the 28th, but in the battalion which had
gone out with Colonel Buller there were very few casualties.
Nevertheless, Zulu-like after a reverse, the two battalions of Wood’s
Irregulars, about 2000 strong, dispersed.
I spent the forenoon, after saying good-bye to the Uys
detachment, in writing a report on the previous day’s
reconnaissance, and letters to the bereaved relatives of those who
had fallen.
At 11 o’clock Raaf reported that the Zulu Army was advancing,
and I sent the officers to recall the wood-cutting parties, and had all
the Trek oxen driven in, except about 200 which had strayed away
from the drivers, whose duty it was to herd them. We got the two
companies back in time for the men to have a hasty dinner before
the attack actually began. The commanding officers asked if the
battalions might not be told to hurry their dinners, but I said, “No;
there is plenty of time,” for by the system enforced in the column
during daylight, as Lord Chelmsford saw five weeks later, our tents
could be struck, and the men be in position in the laager, within
seventy seconds from the last sound of the “Alert.”
At 1.30 p.m. Colonel Buller suggested he should go out and
harry the Zulus into a premature attack, and this he did admirably.
We had shifted camp several times for sanitary reasons. My
friends the Dutchmen could never be persuaded to use the latrines,
although I had one dug specially for them; moreover, Wood’s
Irregulars and the oxen had so fouled the ground as to induce fever,
unless the camp was often shifted. The position in which we
received the attack was on a ridge running in a south-westerly
direction, an under feature of the Ngaba-ka-Hwane Mountain.
The waggons of the 13th Light Infantry formed the right front
and flank, 4 guns were in front of the centre, and the 90th Light
Infantry on the left. The Horse Lines were in the middle, and the
rear face of the Laager was held by the Irregular Horse; 280 yards in
front, on ground 20 feet higher than the Laager, was a redoubt, its
main lines of fire being in a northerly and southerly direction, while
150 yards to the right front of the main Laager was a cattle Laager,
into which we crammed upwards of 2000 oxen. The outer side of it
stood on the edge of a deep ravine, into which the Laager drained.
The wheels of the waggons were securely chained together, and the
space between the forepart of one and the rear of the other was
rendered difficult of ingress by the poles (or dyssel-booms), being
lashed across the intervals.
Two guns under Lieutenant Nicholson were placed en
barbette,
191
at the front end of the Redoubt. The other four guns
came into action under Lieutenant A. Bigge
192
and Lieutenant
Slade,
193
by sections on the ridge, connecting the Redoubt with the
main Laager. The men belonged to Garrison Companies, but I have
never known a battery so exceptionally fortunate in its Subalterns.
Lieutenant Nicholson, standing on the gun platform, fought his guns
with the unmoved stoical courage habitual to his nature.
Major Tremlett was renowned as a fearless sportsman, and both
Bigge and Slade were unsurpassable; they with their gunners stood
up in the open from 1.30 p.m. till the Zulus retreated at 5.30 p.m.,
and by utilising the ridge were enabled to find excellent targets with
cover during the first attack on the southern slope, and later on the
northern slope, and suffered but little loss.
The direction of the Zulu advance was, speaking generally, from
south-east, but when they came in sight they stretched over the
horizon from north-east to south-west, covering all approaches from
the Inhlobane to Bemba’s Kop. When still 3 miles distant, 5000 men
moved round to our Left and attacked the side held by the 90th
Light Infantry, prior to the remainder of the Zulu Army coming into
action. This fortunate circumstance was due to Colonel Buller’s skilful
tactical handling of the mounted men, whom he took out and
dismounted half a mile from the Zulus. The Umbonambi regiment
suffered a galling fire for some time, and then, losing patience,
rushed forward to attack, when the horsemen, remounting, retired
400 yards, and, repeating their tactics, eventually brought on a
determined attack from the Zulu right flank. The Umbonambi
followed up the horsemen until they were within 300 yards of the
Laager, when their further advance was checked by the accurate
firing of the 90th Light Infantry, greatly assisted by the enfilading
fire poured in from the northern face of the Redoubt. I saw a fine
tall Chief running on well in front of his men, until, hit in the leg, he
fell to the ground. Two men endeavoured to help him back as he
limped on one foot. One was immediately shot, but was replaced by
another, and eventually all three were killed.
We now sent the Artillery horses back into the Laager, keeping
the guns in the open, on the ridge between the Redoubt and the
main Laager. I had instructed the officer commanding to serve his
guns till the last moment, and then, if necessary, leaving them in the
open, take his men back to the Laager, which was within 188 yards.
The attack on our Left had so slackened as to give me no further
anxiety, when at 2.15 p.m. heavy masses attacked our Right Front
and Right Rear, having passed under cover up the deep ravine, on
the edge of which the cattle Laager stood.
Some 40 Zulus, using Martini-Henry rifles which they had taken
at Isandwhlana, occupied ground between the edge of the ravine
and the rear of the Laager, from the fire of which they were partly
covered by the refuse from the Horse Lines which had been there
deposited, for, with the extraordinary fertility of South Africa,
induced by copious rains and burning midday sun, a patch of
mealies 4 feet high afforded cover to men lying down, and it was
from thence that our serious losses occurred somewhat later. The
Zulu fire induced me to withdraw a company of the 13th, posted at
the right rear of the cattle Laager, although the front was held by
another half company for some time longer.
I could see from where I stood on the ridge of land just outside
the fort, leaning against the barricade, which reached down to the
cattle Laager, that there were large bodies in the ravine, the
Ngobamakosi in front, and 30 men (leaders) showed over the edge,
endeavouring to encourage the Regiment to leave the shelter, and
charge. I, in consequence, sent Captain Maude to order out two
companies of the 90th, under Major Hackett, with instructions to
double over the slope down to the ravine with fixed bayonets, and to
fall back at once when they had driven the Zulus below the crest.
A 13th man coming away late from the cattle Laager, not having
heard the order to retire, was shot by the Zulus lying in the refuse
heap, and followed by four from the cattle Laager. I was running out
to pick him up, when Captain Maude exclaimed, “Really it isn’t your
place to pick up single men,” and went out himself, followed by
Lieutenants Lysons and Smith, 90th Light Infantry; they were
bringing the man in, who was shot in the leg, when, as they were
raising the stretcher, Smith was shot through the arm. I was firing at
the time at a leader of the Ngobamakosi, who, with a red flag, was
urging his comrades to come up out of the ravine, and assault the
Laager. Private Fowler, one of my personal escort, who was lying in
the ditch of the fort, had asked me, “Would you kindly take a shot at
that Chief, sir? it’s a quarter of an hour I am shooting him, and
cannot hit him at all.” He handed me his Swinburne-Henry carbine,
and looking at the sight, which was at 250 yards, I threw the rifle
into my shoulder, and as I pressed it into the hollow, the barrel being
very hot, I pulled the trigger before I was ready,—indeed, as I was
bringing up the muzzle from the Zulu’s feet. Hit in the pit of the
stomach, he fell over backwards: another leader at once took his
place, cheering his comrades on. At him I was obliged to fire,
unpleasantly close to the line of our officers leading the counter
attack. I saw the bullet strike some few yards over the man’s
shoulder, and, laying the carbine next time at the Zulu’s feet, the
bullet struck him on the breastbone. As he reeled lifeless backward,
another leader seized and waved the flag, but he knelt only, though
he continued to cheer. The fourth shot struck the ground just over
his shoulder, and then, thinking the carbine was over-sighted,
194
I
aimed on the ground 2 yards short, and the fifth bullet struck him on
the chest in the same place as his predecessor had been hit. This
and the counter attack so damped the ardour of the leaders that no
further attempt was made in that direction, although several brave
charges were made to the south of the cattle Laager, against the
right flank of the Redoubt. While I was firing at the leaders of the
Ngobamakosi Regiment, who, from the ground falling away towards
the ravine, were out of sight of the main Laager, the two companies
90th Light Infantry came out at a steady “Double,” Major Hackett
leading, guided by Captain Woodgate, who knew exactly where I
wished the companies to go, and how far the offensive movement
was to be carried out. Lieutenant Strong, who had recently joined
us, ran well in front of his company, sword in hand, and the Zulus
retired into the ravine. The companies, however, were fired on
heavily from the refuse heaps, at 350 yards range, and Major
Hackett was shot through the head; Arthur Bright fell mortally
wounded, and the Colour-Sergeant of Bright’s company, Allen, a
clever young man, not twenty-three years of age, who had been
wounded in the first attack, and, having had his arm dressed,
rejoined his company as it charged, was killed.
The Umcityu and Unkandampenvu had charged so determinedly
over the open on our Left front, as had part of the Ngobamakosi up
the slope to the Redoubt, from the south side of the cattle Laager,
that I did not at first realise the full effect of Hackett’s counter
attack, and apprehended the mass still crouching below the crest
would rush the Right face of the Laager. They would have had some
200 yards to pass over from the edge of the ravine to the waggons,
but, owing to the ground falling rapidly, would have been under fire
from the Laager for 100 yards only. I therefore went into the main
Laager, being met by Colonel Buller, who asked me cheerily for what
I had come, and I replied, “Because I think you are just going to
have a rough and tumble”; but Hackett’s charge had done even
more than I had hoped, and having looked round I went back to my
position just outside the fort.
At 5.30 p.m., when the vigour of the attack was lessening, I sent
Captain Thurlow and Waddy’s companies of the 13th Light Infantry
to the right rear of the cattle Laager, to turn out some Zulus who
were amongst the oxen, which they had, however, been unable to
remove; and I took Captain Laye’s
195
company to the edge of the
krantz on the right front of the Laager, where they did great
execution with the bayonet amongst the Undi Regiment, who were
now falling back. I then sent a note to Buller, asking him to take out
the mounted men, which he did, pursuing from 5.30 p.m. till dark,
and killing, as it happened, chiefly the Makulusi tribe, who had been
his foes on the previous day.
When the enemy fell back in the direction in which they had
come, they were so thick as to blot out all signs of grass on the
hillside, which was covered by their black bodies, and for perhaps
the only time in anyone’s experience it was sound to say, “Don’t wait
to aim, fire into the black of them.”
At 3 a.m. on the 30th, one or two shots from the Outpost line
roused the camp, and the Colonial corps opened a rapid fire to the
Front, immediately over the heads of the two line battalions and
artillery, who stood perfectly steady. Rain was falling, so, while
Maude was ascertaining the cause of the firing, which was a Zulu
who, having concealed himself till then, jumped up close to one of
our sentries, I sat in an ambulance near the battery until the
Colonials having put three bullets into the top of it, I thought it
would be better to get wet than be shot by our own men. After five
minutes the firing was stopped. The scare was excusable, for the
nerves of the mounted men had been highly strung for some hours,
a fourth of those who had ridden up the Inhlobane having been
killed.
In the next few days we buried 785 men within 300 yards of our
Laager, which we were afterwards obliged to shift on account of the
number of bodies which lay unseen in the hollows. We learnt after
the battle that when the Zulus saw our tents go down they thought
it was in preparation for flight, and that unsteadied their Right
Wing.
196
They never fought again with the same vigour and
determination.
The Line battalions were very steady, expending in four hours on
an average 33 rounds a man; though that evening I heard that some
of them had thought the possibility of resisting such overwhelming
numbers of brave savages, 13 or 14 to one man, was more than
doubtful. I had no doubt, and lost all sense of personal danger,
except momentarily, when, as on five occasions, a plank of the
hoarding on which I leant was struck. This jarred my head, and
reminded me that the Zulus firing from the refuse heap in the right
rear of the Laager were fair shots. A few had been employed as
hunters, and understood the use of the Martini rifles taken at
Isandwhana.
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Practical Embedded Controllers Design and Troubleshooting with the Motorola 68HC11 IDC Technology Paperback 1st Edition John Park

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  • 5. Practical Embedded Controllers Design and Troubleshooting with the Motorola 68HC11 IDC Technology Paperback 1st Edition John Park Digital Instant Download Author(s): John Park ISBN(s): 9781417505692, 1417505699 Edition: 1 File Details: PDF, 18.73 MB Year: 2003 Language: english
  • 7. Practical Embedded Controllers: Design and Troubleshooting with the Motorola 68HC11
  • 8. Titles in the series Practical Cleanrooms: Technologies and Facilities (David Conway) Practical Data Acquisition for Instrumentation and Control Systems (John Park, Steve Mackay) Practical Data Communications for Instrumentation and Control (Steve Mackay, Edwin Wright, John Park) Practical Digital Signal Processing for Engineers and Technicians (Edmund Lai) Practical Electrical Network Automation and Communication Systems (Cobus Strauss) Practical Embedded Controllers (John Park) Practical Fiber Optics (David Bailey, Edwin Wright) Practical Industrial Data Networks: Design, Installation and Troubleshooting (Steve Mackay, Edwin Wright, John Park, Deon Reynders) Practical Industrial Safety, Risk Assessment and Shutdown Systems for Instrumentation and Control (Dave Macdonald) Practical Modern SCADA Protocols: DNP3, 60870.5 and Related Systems (Gordon Clarke, Deon Reynders) Practical Radio Engineering and Telemetry for Industry (David Bailey) Practical SCADA for Industry (David Bailey, Edwin Wright) Practical TCP/IP and Ethernet Networking (Deon Reynders, Edwin Wright) Practical Variable Speed Drives and Power Electronics (Malcolm Barnes)
  • 9. Practical Embedded Controllers: Design and Troubleshooting with the Motorolla 68HC11 John Park ASD, IDC Technologies, Perth, Australia
  • 10. Newnes An imprint of Elsevier Linacre House, Jordan Hill, Oxford OX2 8DP 200 Wheeler Road, Burlington, MA 01803 First published 2003 Copyright  2003, IDC Technologies. All rights reserved No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1T 4LP. Applications for the copyright holder's written permission to reproduce any part of this publication should be addressed to the publisher British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library ISBN 07506 58029 Typeset and Edited by Vivek Mehra, Mumbai, India (vivekmehra@tatanova.com) Printed and bound in Great Britain Special thanks to Industrial Automation www.cs.jcu.edu.au/~gregory/hc11/ All photos in this book courtesy of Cursor Magic www.cursormagic.com photos@cursormagic.com For information on all Newnes publications, visit our website at www.newnespress.com
  • 11. Contents Preface xiii 1 Introduction 1 1.1 Microcontroller introduction 1 1.2 Microcontroller design and functions 3 1.3 Assembly language programming 5 1.4 Inputs and outputs 7 1.5 Data communication 8 1.6 Noise reduction 9 1.7 Grounding solutions 10 1.8 Installation techniques 11 1.9 Conclusion 12 2 Microcontroller basics 13 2.1 Introduction 13 2.2 Number systems —binary, hex, and decimal 17 (OZYJOHOZYTOHHRKYH_ZKY]UXJYGTJRUTM]UXJY )UTKXYOUTLXUSHOTGX_ZUNK^GJKIOSGR '9)//NK^GJKIOSGRGTJ()* )UTKXZOTMLXUS'9)//ZU()*GTJ.+ 2.3 Gates —AND, OR, XOR and NOT gates 20 '4*MGZKYmVN_YOIGRGTJOXZ[GR 58MGZKYmVN_YOIGRGTJOXZ[GR 58MGZKYmVN_YOIGRGTJOXZ[GR 45:MGZKYmVN_YOIGRGTJOXZ[GR 2.4 Accumulators, A, B and D 22 'JJXKYYOTMSUJKY 2UGJOTMYZUXOTMGTJZXGTYLKXXOTMGII[S[RGZUXY 'JJY[HZXGIZIUSVGXKOTIXKSKTZGTJJKIXKSKTZ'GTJ( '4*58GTJZKYZHOZY 'XOZNSKZOIGTJRUMOIGRYNOLZOTMGTJXUZGZOTM *GZGGTJHOZZKYZOTM 2.5 Registers —X, Y, the stack and ports 25 :NKGTJ?XKMOYZKXY :NKYZGIQ 6UXZY'()*GTJ+ 2.6 Communications synchronous and asynchronous 28
  • 12. vi Contents 'Y_TINXUTU[YINGXGIZKXIUSS[TOIGZOUTY 9_TINXUTU[YVGIQKZIUSS[TOIGZOUTY 9VKIOL_OTMGY_YZKSmGY_TINXUTU[YYY_TINXUTU[Y 2.7 Power systems 30 .GXJ]GXKYYULZ]GXK .GXJ]GXKXKYKZJKYOMT )56]GZINJUM=UUL 6U]KXLGOR[XKGTJHXU]TU[ZVXUZKIZOUT 2.8 Crystals and oscillator 34 GR[KYYHG[JXGZK +3)GTJ6)(IX_YZGRIRUIQJKYOMT 2.9 Conclusion 37 3 Microcontroller programming 39 3.1 Introduction to programming the microcontroller 39 3.2 Programming structure and specifications 41 6XUMXGSSOTMYZX[IZ[XKY /TV[ZY 3GTOV[RGZOUTULJGZG 5[ZV[ZY ,RU]INGXZY 2UGJOTMGVXUMXGSOTZUGTKGR[GZOUTSUJ[RK+3 9ZKZZOTM[VZNK+3 3.3 Addressing modes 49 3.4 Load, stores and transfers 50 3.5 Arithmetic operations 51 3.6 Logical operations 52 3.7 Shifts and rotates 53 3.8 Index registers and the stack 54 3.9 Condition code register 57 3.10 Branches, jumps, interrupts and calls 57 3.11 BASIC and C++ 58 ('9/) ;YOTM)OTKSHKJJKJVXUMXGSSOTM 3.12 Conclusion 58 4 Microcontroller memory 60 4.1 Introduction to memory 60 4.2 User RAM 61 3OIXUIUTZXURRKXOTZKXTGR8'3
  • 13. Contents vii +^ZKXTGR8'3 4.3 BUFFALO routines, memory map and vectors 64 (;,,'25GYGJKKRUVSKTZZUUR (;,,'25[ZOROZ_Y[HXU[ZOTKY (;,,'25SKSUX_SGV (;,,'25OTZKXX[VZVYK[JUKIZUXY 4.4 Interrupts, vectors and pseudo-vectors 66 9ULZ]GXKYNGXJ]GXKOTZKXX[VZY 3GYQGHRKYTUTSGYQGHRKOTZKXX[VZY 4.5 Control registers 70 3KSUX_SGVVKJ/5 'IIKYYOTMGTJ[YOTMIUTZXURXKMOYZKXY 4.6 EEPROM 71 )RKGXOTMZNK++6853K^GSVRK =XOZOTMZUZNK++6853K^GSVRK 4.7 Conclusion 74 5 Microcontroller inputs and outputs 76 5.1 Introduction to inputs and outputs 76 5.2 Single ended vs differential inputs 77 9OTMRKKTJKJGTGRUMIOXI[OZY 9OTMRKKTJKJJOMOZGRIOXI[OZY *OLLKXKTZOGRGTGRUMIOXI[OZY *OLLKXKTZOGRJOMOZGRIOXI[OZY 5.3 Digital inputs 80 9]OZINYKTYOTMGTJJKHU[TIK 4UXSGRR_UVKT45GTJTUXSGRR_IRUYKJ4)Y]OZINKY +RKIZXUTOIY]OZINKY 5.4 Digital outputs 82 *OMOZGRIUTZXUR (GIQ+3,IG[YKYGTJYUR[ZOUTY 5.5 Analog inputs 84 URZGMKI[XXKTZGTJXKYOYZOKSKGY[XKSKTZ 'TGRUMGTJJOMOZGRLORZKXOTMGTJGSVROLOIGZOUT 4_W[OYZGTJZNKYGSVRKXGZK 8KYUR[ZOUTSGTGMKSKTZ 5.6 Digital control of analog devices 87 (GYOIYZKVVKXSUZUXY 9ZKVVKXSUZUXIUTZXURGTJIUSS[TOIGZOUT 5.7 Keypad interfacing 88 )UTTKIZOTMZNKQK_VGJZUZNKKGR[GZOUTSUJ[RKY+3 8KGJOTMZNKQK_VGJOTYULZ]GXK
  • 14. viii Contents 5.8 LCD interfacing 91 2)*YULZ]GXKYKZ[V =XOZOTMZUZNK2)* 5.9 Conclusion 95 6 Data communications 96 6.1 Introduction to data communication 96 6.2 Basics of serial data communication 97 .OYZUX_ULYKXOGRJGZGIUSS[TOIGZOUTY :NXKKVGXZYULJGZGIUSS[TOIGZOUTY 6.3 Open system interconnection model 100 'VVROIGZOUTRG_KX 9KYYOUTVXKYKTZGZOUTZXGTYVUXZGTJTKZ]UXQRG_KXY *GZGROTQRG_KX 6N_YOIGRRG_KX 6XUZUIURYGTJZNKZNXKKRG_KXSUJKR 6.4 Modes of communications 103 9OSVRK^ .GRLJ[VRK^ ,[RRJ[VRK^ :NKSGYZKXYRGKH[Y :NK)93')*H[Y :NKZUQKTH[YY_YZKS :OSKJY_YZKSY 6.5 RS-232 107 /TZXUJ[IZOUTZU89 ,[TIZOUTULZNKROTKY 89OTYZGRRGZOUTGTJZXU[HRKYNUUZOTM 6.6 RS-485 111 /TZXUJ[IZOUTZU89 89Y89 89OTYZGRRGZOUTGTJZXU[HRKYNUUZOTM 6.7 Fiber optic cables 114 6.8 Fieldbus protocols used in controllers 115 6.9 Conclusion 116 7 Noise reduction 118 7.1 Introduction to noise reduction 118 :NKJKIOHKR 9OMTGRZUTUOYKXGZOU 9U[XIKYULTUOYKmOTZKXTGRYK^ZKXTGR 9OTMRKKTJKJUXMXU[TJKJIOXI[OZY
  • 15. Contents ix 9OTMRKKTJKJSKGY[XKSKTZULMXU[TJKJYU[XIKY 9OTMRKKTJKJMXU[TJKJKW[OVSKTZ *OLLKXKTZOGRTUOYKIOXI[OZY *OLLKXKTZOGRZKYZKW[OVSKTZ )USSUTSUJKTUOYKVXUHRKSY 2U]OSVKJGTIKJXUVYGYTUOYKYU[XIKY :_VKYULK^ZKXTGRR_OTJ[IKJTUOYK 7.2 Conductive coupled noise 127 )UTJ[IZOKTUOYKLXUSK^ZKXTGRKW[OVSKTZ )UTJ[IZOKTUOYKLXUSZXGTYSOYYOUTROTKY 7.3 Capacitive coupled noise 129 )GVGIOZOKTUOYKLXUSGJPGIKTZKW[OVSKTZ )GVGIOZOKTUOYKLXUSIUSS[TOIGZOUTROTKY 7.4 Magnetically coupled noise 130 3GMTKZOIGRR_OTJ[IKJTUOYKLXUSGJPGIKTZIGHRKY 3GMTKZOIGRR_OTJ[IKJTUOYKLXUSGJPGIKTZKW[OVSKTZ 7.5 EMC and noise reduction in PCB design 132 6RGIKSKTZULGTGRUMJOMOZGRGTJVU]KXY[VVR_IOXI[OZY *OMOZGRIOXI[OZJKIU[VROTM -XU[TJVRGTKY *GTJ*,GXGJG_YNOKRJY 7.6 Conclusion 136 8 EMC grounding solutions 137 8.1 Introduction to EMC grounding solutions 137 8.2 EMC grounding 138 -XU[TJYVKIOLOIGZOUTY :_VKYULKGXZNMXU[TJY 8.3 EMC grounding on a PCB 143 6)(JKYOMTXKIUSSKTJGZOUTY :XGIQVRGIKSKTZ ,GXGJG_HU^KY 8.4 Protecting a PCB from lightning 150 6RGIKSKTZULVXUZKIZOUTUTZNK6)( :NK-*:35GTJZXGTYUXH 8.5 Microcontroller equipment ground 153 8.6 Enclosure or safety ground 154 9VOQKJKGXZNMXU[TJY )GHRKZXKTINMXU[TJY :U]KXROMNZTOTMVXUZKIZOUT 8.7 Conclusion 157
  • 16. x Contents 9 Installation and troubleshooting 159 9.1 Introduction to installation and troubleshooting 159 9.2 Connections —screw, crimp and solder 160 9IXK]IUTTKIZUXY )XOSVIUTTKIZUXY 9URJKXOTMIUTTKIZOUTY )UTTKIZUXVXUHRKSYGTJYUR[ZOUTY 9.3 Cable runs and trays 166 3KZGRYVRGYZOIX[TYGTJZXG_Y KXZOIGRX[TYGTJZXG_Y .UXO`UTZGRX[TYGTJZXG_Y 9.4 Cable ties and mounting 169 9.5 Cooling, heating and air conditioning 170 9.6 Wire management in a cable run 171 9.7 Conduit installation 172 9.8 Troubleshooting techniques 173 9.9 Safety considerations 174 9.10 Conclusion 175 10 End notes 176 10.1 Conclusion 176 10.2 CPU design and functions 176 10.3 Assembly language programming 177 10.4 Memory 178 10.5 Inputs and outputs 178 10.6 Data communication 179 10.7 Noise reduction 180 10.8 Grounding solutions 181 10.9 Installation techniques 181 10.10 Final words 182 Practicals 183 Practical 1: Setting up the 68HC11 emulator board 183 Practical 2: Activating LEDs on the EVM 191 Practical 3: Reading switches on the EVM 197 Practical 4: Sending characters to an LCD display 204 Practical 5: Reading keypad input 212
  • 17. Contents xi Practical 6: Using the PAT software 221 Practical 7: Viewing character data transmission 226 Practical 8: Troubleshooting a data communication system 233 Practical 9: Troubleshooting a protocol problem 236 Bibliography 242 Index 243
  • 18. Preface From microwave ovens to alarm systems to industrial programmable logic controllers (PLCs) and distributed control systems (DCSs), embedded controllers are running our world. Embedded controllers are used in most items of electronic equipment today. They can be thought of as intelligent electronic devices used to control and monitor devices connected to the real world. This can be a PLC, DCS or a smart sensor. These devices are used in almost every walk of life today. Most automobiles, factories and even kitchen appliances have embedded controllers in them. The microcontrollers that are at the heart of these and many more devices are becoming easier and simpler to use. But when these devices fail, the solution to the problem needs to be found and repairs done quickly. This book will help technicians, engineers and even the casual user understand the workings of microcontrollers, along with the most common problems and their solutions. This book covers all aspects of embedded controllers but is biased towards troubleshooting and design. The book also covers design, specification, programming, installation, configuration and troubleshooting. After reading this book we hope you will have learnt how to: • Design, set up and program a complete embedded controller development system • Apply the latest techniques in programming these versatile devices • Apply troubleshooting tips and tricks for microcontrollers • Apply the best techniques for installation of microcontrollers • Fix problems due to electrical noise and interference • Design correctly the first time to avoid grounding and EMC problems • Choose and configure the correct software Typical people who will find this book useful include: • Electronic technicians and engineers • Instrumentation and control engineers and technicians • Process control engineers and technicians • Electrical engineers • Consulting engineers • Process development engineers • Design engineers • Control systems sales engineers A basic knowledge of electrical principles is useful in understanding the concepts outlined in the book, but the contents are of a fundamental nature and are easy to comprehend. The structure of the book is as follows. Chapter1 /TZXUJ[IZOUT This chapter gives a brief overview of the main components of a microcontroller. Chapter 2 3OIXUIUTZXURRKX HGYOIY. A review of the basics of this device with a discussion on number systems, Boolean logic, accumulators, registers, data communications, power systems, crystals and oscillators, is done in this chapter.
  • 19. xiv Preface Chapter3 3OIXUIUTZXURRKXVXUMXGSSOTM A review of the simple techniques involved in programming a microcontroller with a discussion on the various programming issues such as programming structures, addressing modes, operations and finally a short comparison of C++ and BASIC, is done in this chapter. Chapter4 3OIXUIUTZXURRKXSKSUX_ The main types and techniques in the effective use of memory such as user RAM, BUFFALO routines, interrupts, control registers, and EEPROM are assessed here. Chapter5 3OIXUIUTZXURRKX OTV[ZYGTJU[ZV[ZY. Analog and digital inputs, keypad and LCD interfacing are described here. Chapter6 *GZGIUSS[TOIGZOUTY This important topic is broken down into a discussion on the fundamentals, the OSI model, modes of communication and RS-232 and RS-485. Chapter 7 4UOYK XKJ[IZOUT This chapter gives an overview of noise reduction and a discussion on conductive, capacitive, and magnetically coupled noise. Chapter8 +3)MXU[TJOTMYUR[ZOUTY The most important features of grounding (and protection from lightning) to protect the microcontroller from the effects of EMC are discussed here. Chapter9 /TYZGRRGZOUTGTJZXU[HRKYNUUZOTM This chapter is a short discussion on connections, cable runs and trays, wire management and troubleshooting techniques. Chapter10 +TJTUZKY. A wrap discussion on the issues discussed in the earlier chapters with a few words on assembly language programming, memory, inputs and outputs, data communication, noise reduction and grounding solutions and finally installation techniques.
  • 20. Introduction Objectives When you have completed this chapter, you will be able to: • Describe the basic parts and functions of microcontrollers • Explain what assembly language is and how it is used • Describe memory mapping • Describe the basics of inputs and outputs • Describe what types of data communications controllers use • Explain noise reduction and its relationship to good signals • Describe potential grounding problems 1.1 Microcontroller introduction Embedded controllers are used in most commercial and industrial electronic equipment. The sheer volume of embedded controllers used in the world drives us to understand how they work and then how to troubleshoot and repair them. The microcontrollers and support chips used in these controllers are becoming smarter and easier to use. This is bringing the design and use of embedded controllers to more and more engineers hence the need for a good understanding of what embedded controllers are and how to troubleshoot them. Embedded controllers are intelligent electronic devices used to control and monitor devices connected to the real world. This can be a microwave oven, programmable logic controller (PLC), distributed control system (DCS) or a smart sensor. These devices are used in almost every walk of life today. Most automobiles, factories and even kitchen appliances have embedded controllers in them. As time goes on and electronic devices get smarter and smaller, the embedded controller will be in or associated with everything we touch throughout the day. Early embedded controllers contained a CPU (central processing unit) and a multitude of support chips. As time went on, support chips were included in the CPU chip until it became a microcontroller. A microcontroller is defined as a CPU plus random access memory (RAM), electrically erasable programmable read only memory (EEPROM),
  • 21. 2 Practical Embedded Controllers inputs/outputs (I/O) and communications (Comms). The embedded controller is a microcontroller with peripherals such as keypads; displays and relays connected to it and is often connected to other embedded controllers by way of some type of communication system. Figure 1.1 Embedded controller development board Figure 1.2 Keypad for embedded controller Electronic equipment is becoming more and more susceptible to noise and other outside influences that can cause catastrophic problems. To be able to troubleshoot and ultimately repair the embedded controller it is not only necessary to understand the inter-workings of the embedded controller but also the external forces that can affect the normal operation of the controller. This may be noise, bad connections or incorrect installation of the system. Often simple things like bad grounds or incorrectly made connections can cost the user hundreds, if not thousands of dollars in down-time. Although the embedded controller ultimately can be a complicated device, when disassembled into its basic parts it becomes simple, clear and easy to understand.
  • 22. Introduction 3 1.2 Microcontroller design and functions The microcontroller is a direct descendent of the CPU, in fact every microcontroller has a CPU as the heart of the device. It is therefore important to understand the CPU in order to ultimately understand the microcontroller and embedded controller. The central processor unit (CPU) is the brain of the microcontroller. The CPU controls all functions and uses the program that resides in RAM, EEPROM or EPROM to function. The program may reside in one or more of these devices at the same time. Part of the program might be in RAM while another might be in EEPROM. Figure 1.3 68HC11 CPU A program is a sequence of instructions that tell the CPU what to do. These instructions could be compared to instructions a teacher may give to a student to get a desired result. The instructions sent to the CPU are very, very simple and it usually takes many instructions to get the CPU to do what is necessary to accomplish a task. Upper level programming languages like BASIC and C++ include multiple instructions in one command to speed up the process of programming the CPU. Just like the human brain the CPU is made up of regions that have specific functions. These components are controlled by the program instructions. The main components of the microcontroller are as follows: • CPU • External address bus • External data bus • External control bus • Internal RAM • Internal ROM • Internal ERPROM • Internal EEPROM • Internal registers • Digital inputs • Counter inputs • Digital outputs • Analog inputs • Serial data communications • Parallel ports
  • 24. Introduction 5 This may seem like a large number of components, but grasping the complete microcontroller system becomes very easy once each of the individual components is understood. In a microcontroller, the CPU uses an internal parallel address and data bus to communicate with memory components like RAM, EEPROM and ROM. It also uses this internal bus to talk to communication systems, I/O ports and registers. The internal microcontroller memory components such as RAM, ROM, EPROM and EEPROMs are used to store (either temporary or permanently) data and program instructions. The internal registers are used to manage temporary bytes of data, like addressing for the program. The serial communications section lets the microcontroller communicate with other devices via a communication standard such as RS-232 or RS-485. The parallel ports such as A, B, C, D and E can be used to transfer data to and from external memory chips or devices. These ports can be used to read and write to devices like keyboards and LCDs. An external parallel data bus can also be used by the microcontroller to activate or read external devices like switches, relays, and LEDs. The digital I/O and analog inputs are used to bring inputs and outputs to and from the microcontroller. 1.3 Assembly language programming Often when assembly language programming is mentioned programmers groan that it is all too hard and difficult. Assembly programming is actually easy and simple (almost too easy). The two best things about assembly language programming is the control it gives the programmer over the microcontroller and the minimal instructions needed to do the job. Using BASIC or C++ is compared by some to using a chain saw to peel an egg. From a functional point of view, using BASIC, C++ or some other high-level language is simple and straightforward but it does use a huge amount of memory compared to assembly language. This limits the size of the program that the programmer can load into the microcontroller. Chip manufactures have gone to great lengths to include RAM, ROM and EEPROM on board the microcontroller. This memory is usually only hundreds of bytes. Programming the microcontroller without using external memory chips is almost impossible using BASIC or some other high level languages. Therefore, assembly language becomes the only option. Programming is often compared to painting a picture. One difference though is that in art it is often unclear when the painting is finished. In programming the program is done when it does what it was designed to do. This can be defined and specified before the program is written. Strangely enough, this step of exacting specification is often overlooked and the program is just let to evolve. As in most endeavors, preparation is everything. The participants in the programming process should spend a large amount of time preparing for the writing of the program. In its simplest form, the program is a sequential set or list of instructions that tell the microcontroller what to do. Each step in the process is done in a specific order. The process is divided up into separate individual sections called subroutines. A subroutine is a small program that performs some tiny function within the overall program. An example of this could be starting a car. The sequence of events that are used to start a car could be called a subroutine within the overall program of driving the car. It is a very specific and defined sequence of acts or instructions. It is stand-alone and can be repeated when necessary. In programming language, it would go something like...
  • 25. 6 Practical Embedded Controllers Figure 1.5 Starting the car Jump to ‘Start the Car’ Start the Car Put key in ignition Started Turn key clockwise to the start position Has the car started? If the car has started, release the key and go to ‘End’ If not, continue to hold the key in the start position Loop to ‘Started’ End Return to main program (i.e. drive the car) Put Key in Ignition TurnClockwise Drive the Car Start the Car Has T he Car Started? No Yes Figure 1.6 Flow chart to start the car
  • 26. Discovering Diverse Content Through Random Scribd Documents
  • 27. companies crossing the Intombe River, 5 miles from Luneberg, had camped at the station when the water rose, and the 5th Company was unable to cross. A raft was employed, and one-third of the company had reached the west side of the stream of the river at nightfall. Half an hour before daylight next day an attack was made by Umbeline, assisted by Manyoba’s 174 tribe. Nearly every one on the east bank of the river was assegaied, many in their tents, and the Zulus, taking to the water like otter hounds, crossed and endeavoured to overwhelm the 34 men on the Western bank. Some 10 of these, however, were not only skilfully but courageously handled by Sergeant Booth, who successfully brought the party back. In all 40 of our men were killed. I went over at daylight to the scene—40 miles distant—to inquire into the disaster, and to ensure our system for security being adopted for the future, returning in the afternoon to camp, as I had arranged a long ride for next day. Uhamu, a brother of Cetewayo’s, came into our camp 175 in the Cape cart which I sent for him, he being so enormously bulky that it was difficult to find a horse to carry him. He had made many appointments, but in the procrastinating Zulu fashion had failed for various reasons to keep them, until Colonel Buller had ceased to believe in his being willing to come over to us. Finally he went to my Assistant Political Agent, Norman Macleod, in Swaziland. He was no sooner in our camp than he asked me if I would be good enough to go after his wives. “How many are there, Uhamu?” “I don’t know but about 300,” he replied vaguely. “But you have got two now with you,” I urged. “These are only slaves,—I should like to have the others.” “I am not willing to take the responsibility of escorting all your wives unless you will come with me.” “Oh, in such a case, Great Commander, I would sooner do without them.” Uhamu’s head Place was in a rugged country, 45 miles from our camp, between the Black Umvolosi and Mkusi Rivers, and Ulundi being within 40 miles of the kraal, there was the possibility of our return being cut off if either of Uhamu’s men let it be known, by
  • 28. Cetewayo’s adherents, they were collecting the women in anticipation of our arrival. Looking, however, to the Political effect of getting out the tribe, I decided to go down, and on the 14th March started with 360 mounted men under Buller, and 200 of Uhamu’s men, many of whom had fought against No. 3 Column at Isandwhlana. Some of my officers objected to my leaving Buller and the White men and accompanying Uhamu’s people, by a short cut over the Zunguin Mountain, which would save three hours’ travelling. I argued that there was absolutely no danger while their Chief was located in my camp, especially as the men looked forward to bringing their wives and children back with them. I took with me Captain Woodgate, 176 Mr. Llewellyn Lloyd, 177 my interpreter, Lieutenants Bigge, 178 Bright, 177 and Lysons. 179 We joined Colonel Buller under the Inhlobane, down the slopes of which some aggressive Zulus came, and fired at us at long ranges. I allowed two or three men to return the fire, and then had two shots myself, and the bullets falling amongst the Makulusi—for they occupied the mountain, silenced their fire. About 2 p.m. we saw a few cattle to the south of us, and Piet Uys despatched his two boys, aged fifteen and thirteen, with half a dozen men to drive them to us. Master Dirks Uys shot a Zulu. When the father heard the firing he tried to look unconcerned, and was too proud to ask me (for his eyes were not as good as mine) if I could see what the lad was doing. Lysons told me later that he kept on repeating, “Are they coming back yet?” The men brought back about 100 head of cattle, and I said to my friend Piet, “I am glad the lad has come back. I saw that you were nervous.” “Yes,” he said, “I am always nervous if I am not there myself,” a feeling which I understood. Nevertheless he risked them in every skirmish, though the warmth of his affection for his youngest born—Piet was a widower—was evident. In an argument he said something which I thought unworthy of the bigness of his character, and I remarked, “Why, you risk Dirks for us, you should not talk of farms and
  • 29. property”; and he replied, his eyes filling, “You are quite right, I would not give Dirks for all Zululand!” An hour or two later Piet called out that he saw Zulus, and galloped off with his two boys, but on this occasion nothing happened, for the Zulus he had sighted were some of Uhamu’s men, who, taking advantage of our presence, were coming to join us. We marched steadily till sunset, when we off-saddled for an hour, to let the horses graze, and, moving off again at dusk, at 9.30 p.m. reached the spot I had arranged with Uhamu, having taken three hours to pass over the last seven miles. We descended a mountain by a goat path, and all the Europeans dismounted; but I, being tired from having been touched by the sun in the forenoon, threw the reins on my pony’s neck and let him choose, or rather feel, the path,—it was too dark to see, and we got down without accident. At sunset Uhamu’s 200 men who accompanied me had asked me to stop, declaring they were tired. This I refused, and when we got down they had nearly cooked their food, having passed down by a still steeper but shorter path. Before I went to sleep I had some of the women, for whom I came brought out of a cave three miles off, as I foresaw there would be delay next morning, and every hour added to the chance of our being caught by some of Cetewayo’s regiments. During the night I sent 6 miles away to some caves where I heard there were more women, being unable to sleep soundly, although greatly fatigued, for one troop of the Frontier Light Horse, linked 180 in line, nearly walked over me, after they had eaten all the grass within reach. Buller came and pulled them away; indeed, every time I awoke in the night I saw him walking up and down, for he felt we were in a precarious position. At daylight we shook ourselves, and began to start—a long stream of humanity. The Refugees numbered between 900 and 1000, men, women, and children. Many of the latter, although only five years old, walked from 6.30 a.m. till 9.30 p.m., when they had covered 30 miles. I sent Captain Barton on in front, while Colonel
  • 30. Buller and I remained behind. At 8.30 we were assured by Messrs. Calverley and Rorke—two traders who had often been in the district —that we had got the whole of the women and children. My engagement was that I would remain till daylight,—that is, six o’clock. At 8.30 Colonel Buller marched, a small Rear guard, remaining with me till 10.30, as even then stragglers were coming in, the last few being shot at, and two assegaied in our sight but too far off for us to save them. My friend Buller had stoutly declared that he would have nothing to do with the verminous children, nevertheless during the march I more than once saw him with six little black bodies in front of and behind his saddle, children under five years of age. As we passed under the Inhlobane, the Makulusi tribe, which had been reinforced by one of Cetewayo’s regiments from Ulundi, fired a few shots at us without any effect, and we bivouaced at nightfall on a small effluent of the White Umvolosi, where Vryheid now stands. Next morning I started the procession at daylight, remaining myself on the top of the Zungu in range to see the Rear guard into camp. I had sent in for all mule waggons available, to save the children a farther walk of 10 miles, and was waiting at the top of the pass, up which we had climbed on the 22nd January, for a dozen women who were loitering half up the mountain. It was past noon when I desired Piet Uys to descend and hurry them up, holding his horse for him, for it was too steep to ride down. When he returned he said, in his curious mixture of Dutch, German, and English, “Kurnall, die vrow sie sagt now too sick, presently have baby, then come quick.” “Piet,” I exclaimed, “oughtn’t we to send some of these women back to see after her?” “Not necessary, Kurnall, she come.” Calling Mr. Llewellyn Lloyd, my interpreter, I apprised him of the situation, and said, “You are not to go into camp until that woman gets there.” Finally, waiting for the waggons longer than I expected, I did not reach camp till 5 p.m., and, having had nothing to eat or drink since our morning cocoa at daylight, I was annoyed to see Lloyd sitting in his tent with a cup of tea, and observed in a
  • 31. somewhat irritable tone, “I thought I told you not to come into camp until the woman who was about to bring a baby into the world had arrived. “Yes, quite so,” he replied, “but she has been in camp a long time. Half an hour after you told me, she passed me like one of Waukenphast’s pictures, doing five miles an hour easily, and I, suspecting that she had left her baby in the rocks, made her angry by insisting on seeing it, but she had it right enough under her arm.” Throughout the weeks of waiting for reinforcements I had frequent letters of encouragement from the High Commissioner and Lord Chelmsford; the latter writing to me frankly, said I had caused irritation amongst the local Civil authorities by the insistent tone of my communications. I have no doubt that this was accurate, but on the other hand many were supine, some actually obstructive. I was unable to induce the Field Cornet of Wesselstroom to take any effectual steps to send back 400 men who had deserted, out of the 600 enlisted when we crossed the border. The Transvaal Boers rejoiced in our misfortune, and openly stated that they intended to rise; some of the Natal authorities objected to my sending any Refugees into the Colony, advancing the most absurd reasons. The Political Agent, sent from Pretoria to Utrecht to assist me, instead of doing so wrote at length that he was advised that the action of the Administrator of the Transvaal, in putting the Commando law in force for the Kafirs, was illegal. The Civil authorities on the Natal and Transvaal border clamoured for protection, and urged me, but in vain, to fall back to ensure the protection of certain villages. The Utrecht Landdrost begged me to encamp close to that village, while the Landdrost of Wesselstroom, the chief village of the Wakkerstroom district, spent much time in endeavouring to persuade me to encamp in front of his village. When I intimated that I was not interested in Utrecht, as I had ample supplies at Balte Spruit, they expressed anxiety for the safety of that depot, and importuned Lord Chelmsford on the subject, who referred the correspondence to me, and to whom on the 3rd March I wrote in reply: “I have often
  • 32. considered your proposition about the Zulus masking this position, and going on to attack Balte Spruit and Utrecht. I do not believe they are equal to such a manœuvre, and are incapable of remaining in presence of a Force without attacking it or running away. If all our mounted men were absent I should feel anxious, but so long as they are here I could always make the Zulus attack us by sending the mounted men to follow them if they marched to Balte Spruit. I doubt Cetewayo turning out more than 30,000 men; if he does, he would do better to send 20,000 here and 10,000 against you. Moreover, the moral effect of our being in Zululand is considerable, both on the Swazis and the Boers.” I discussed fully in this letter a scheme I had long considered about attacking the Inhlobane, but when Colonel Buller burnt the Makulusi Kraals, bringing away 500 of their cattle, the necessity was less apparent, and I did not recur to the plan until asked to take pressure off the Force relieving Ekowe. The Civil authorities were not, however, the only demoralised people. The General, in deference to the apprehensions of the inhabitants, sent a garrison to hold a village 30 miles behind our camp, and the Commanding officer marched round by Newcastle, adding 12 miles to his journey to avoid crossing a bit of Zululand 10 miles on the safe side of Kambula, and on arrival pitched his men’s tents inside the cattle laager, which was several feet deep in manure; he became sick in a few days and went away. The next senior officer, on hearing of the disaster to the Company of the 80th, on the Intombe 45 miles distant, recalled a Company which was 10 miles behind our camp, at Kambula, for fear of its being surprised, although there were still four companies 80th Regiment at Luneberg, and another company from our camp, coal digging, all between him and the enemy. Indeed, the overweening confidence felt by many before the war had now changed into unreasoning apprehension. The one great heroic figure throughout the time when men’s minds were depressed was undoubtedly the High Commissioner, Sir Bartle Frere. He spent many days and nights in supporting all my demands, and in coercing unwilling and timorous Civil subordinates.
  • 33. With great address and moral courage he prevented an outbreak of the Boers, projected after the destruction of No. 3 Column. On the 12th March I took the opportunity, when acknowledging the thanks by the High Commissioner and the General, to point out how much I owed to the Staff officers, Mr. Llewellyn Lloyd, my interpreter and Assistant Political Agent, Captain Ronald Campbell of the Coldstream Guards, Captain Vaughan, R.A., Director of Transport, and Mr. Hughes, Assistant Commissary-General, who worked literally day and night to carry out my wishes. The difficulties of transport for the increased force, which was coming out to reinforce Lord Chelmsford’s command, being always before me, I wrote urging that we should purchase sufficient at once, as hiring was not only extravagant but impracticable. The Chief replied on the 14th March that he had handed my offer to provide waggons to the Commissary-General, and was surprised that he did not jump at the offer, but added, “I do not like to interfere with his arrangements; please do as you like best yourself. I congratulate you on the surrender of Uhamu, the entire credit of which belongs to you. You can do anything you like with your column; if you like to attack the Inhlobane, pray do so.” I had previously asked permission to send officers to the Free State to purchase mule transport, foreseeing that the final advance on Ulundi might be delayed until the grass on the veldt would no longer suffice for oxen, and thus render the movement impossible without mule transport. After writing in vain repeated reminders for five weeks, I decided to act on the qualified sanction of my Chief in his letter of the 14th, “Please do as you like best yourself”; and on the 23rd sent two officers to the Free State, giving the senior, Captain Bradshaw, 13th Light Infantry, a cheque for £56,000, drawn on the Standard Bank of South Africa. They did very well indeed, enabling me to supply the 2nd Division, without which, as Lord Chelmsford wrote later, the advance would have been impossible. The only comment made by the War Office on my action was to the effect that, as the money could not be all expended at once, I
  • 34. ought to have drawn two cheques, each for £28,000 at different dates, as I should thus have saved the amount of interest unnecessarily paid to the Bank. In my reply, while admitting my mistake, I remarked I had already spent for the Government over £50,000 without the assistance of a Paymaster, and it was therefore reasonable to debit the salary of such an officer against the amount of interest I had unnecessarily incurred. The day Captain Bradshaw left was one of some anxiety. I had arranged a raid, by all the mounted men, in a North-Easterly direction to the Southward of Luneberg, to destroy the crops of one of our most troublesome foes. A convoy of 40 waggons was going in the opposite direction, South-South West to Balte Spruit, escorted by Infantry, and there was a working party, with an Infantry escort, employed in removing Potter’s Store, which I had purchased and was moving from the Pemvane River to Balte Spruit. When we stood to our arms an hour before daylight the fog was so thick that we could not see 40 yards, and it did not clear off till the forenoon. I decided, however, to let the movement proceed as ordered, preferring the risk of surprise while I was present, to any which might occur in my absence. Next morning, when I saw the convoys safe back in camp, I started and, overtaking Colonel Buller’s 300 men, and 500 of Wood’s Irregulars, reached Luneberg at sunset on the 24th. Next day we spread out over the basin of the Intombe River, cultivated by Umbiline’s tribe, who were Zulus, although he was a renegade Swazi. We destroyed all the crops we could, and after two long days’ work returned, on the evening of the 26th, to Kambula Hill. In a letter dated the 19th Lord Chelmsford called my attention to a paragraph in a Maritzburg newspaper, from a Correspondent with No. 4 Column, alleging that I was fretting at the inaction imposed on me by the General, and wrote, “You can undertake any operations you like, and I shall hear of it with pleasure. I hear all Cetewayo’s army will be concentrated about Ekowe in a few days, so we shall have a hottish encounter.” I replied on the 27th, “I do not often see
  • 35. the letters of the Correspondent, and hold no communication with him. If I did I should certainly tell him I am perfectly unfettered, your only action being to support me in every way. Buller has started, and at 3 p.m. I follow, to try to get up the Inhlobane at daylight to-morrow. I am not very sanguine of success. We do not know how steep the Eastern end may be, but I think we ought to make a stir here, to divert attention from you, although, as you see by our last reports, it is asserted that you have only Coast tribes against you, and that all Cetewayo’s people are coming here.” In the forenoon of the 27th March, the two columns which were to attack the Inhlobane at daylight next morning marched; I followed in the evening, intending to lie down 5 miles under the Western edge of the Inhlobane. The more important part of the operation was intrusted to Colonel Buller, under whose orders I placed the two battalions of Wood’s regiment. The 1st battalion, under Major Leet, bivouacing near the White Umvolosi, where Vryheid now stands, was intended to ascend the Western end of the mountain; both columns were to get as high up as they could before daylight on the 28th. In the orders I stated that, as Cetewayo was said to be advancing with his whole army, scouts were to be sent to the South and South-West, to watch the avenues of approach from Ulundi. I took with me Mr. Lloyd, Assistant Political Agent and Interpreter, Captain the Honourable Ronald Campbell, Coldstream Guards, and Lieutenant Lysons, 90th Light Infantry, Orderly officer, my personal escort, eight mounted men of the battalion, and seven mounted Zulus under Umtonga, a half-brother of Cetewayo’s, whom the father, Umpande, had originally designated to succeed him. Before I went to sleep I had a long talk with Piet Uys, who was to accompany Colonel Buller, and had stayed behind to see me, while the Colonel had bivouacked 5 miles farther to the east. Mr. Potter, a Captain in the 1st Battalion, Wood’s Irregulars, also came to me. Both men knew the Inhlobane, and Potter had often been up on it. I asked whether, if we should have the bad luck after taking the mountain to see Cetewayo’s army advancing, we could get down on
  • 36. the North side, and Mr. Potter assured me that we could,—by leading our horses. Piet Uys was confident that Colonel Buller would get up, without serious loss, and we agreed that, except in the probable contingency of the Zulu main army coming in sight, our operation ought to be a success; then Piet turning to me, said, “Kurnall, if you are killed I will take care of your children, and if I am killed you do the same for mine.” We had heard, indeed, for several days that Kambula was to be attacked, but were informed that the Zulu Army could not leave till the 27th, as there had been a delay in “doctoring” one of the largest regiments. This was inaccurate. It had started on the 25th March.
  • 37. A CHAPTER XXX 1879—THE INHLOBANE, 28TH MARCH The ride to Death—Buller surmounts the mountain— Fate of two heroic Coldstream Officers—Campbell and Barton—Major Leet, V.C.—Chicheeli’s description of Barton’s death—Buller’s heroism—Ronald Campbell as tender hearted as he was brave. T 3 a.m. on the 28th I rode Eastward, with the Staff officers and escort. Captain Campbell and I were silent, but the two younger men chattered till I wondered whether their voices could reach the Zulus on the Inhlobane. When Ronald Campbell spoke on Lloyd’s challenge for his thoughts, he replied, “I am hoping my wife is well and happy.” Lloyd and Lysons, jubilant at the prospect of a fight, remarking on my silence, asked, “Are you doubtful, sir, of our getting up to the top of the mountain?” “Oh no, we shall get up.” “Then, of what are you thinking?” “Well, which of you will be writing to my wife to-night, or about which of you young men I shall be writing to parents or wife?” Colonel Buller, to avoid risk of being surprised, had shifted bivouac twice during the night, but at daylight we struck his track and followed it. We met a Squadron of his Force coming Westwards, the Commandant having lost his way the previous night, and I directed him to move to the sound of the firing, which was now audible on the North-East face of the mountain, where we could just
  • 38. discern the rear of Colonel Buller’s column mounting the summit. I followed the Squadron, but when it came under fire, as it did not advance rapidly, I passed to the front, the track at first being easy to follow, from worn grass and dead horses of Colonel Buller’s command lying on it. Hard rock now replaced the beaten down grass, and as we came under fire I unconsciously, by leading directly towards the rocks whence the bullets came, missed the easier gradient, up which Buller’s men had ridden, losing only one officer. The ground was now steep and very rugged, so we dismounted and put the horses of my White and Black escort in a cattle kraal, the walls of which were 2½ feet high. Campbell invited me to leave my horse. I said, “No; I am a bad walker,” and pulled it after me, Mr. Lloyd being close on my left hand. Half a dozen of the foremost of the Irregulars had dismounted sooner, and followed me until Lloyd and I were within 100 feet of the crest of the mountain, and we came under well-directed fire in our front, and from both flanks, the enemy being concealed behind huge boulders of rock. The men of the Squadron 200 yards behind us now opened fire, and Mr. Lloyd said, “I am glad of that, for it will make the Zulus shoot badly.” He had scarcely spoken these words when a Zulu rose up from behind a rock 50 yards above us, and, touching Lloyd with my elbow, I observed, “He won’t hit us in the face,” for he laid his gun directly at my waistbelt. He fired, and Lloyd fell back, exclaiming, “I am hit!” “Badly?” “Yes, very badly; my back’s broken!” I tried to lift him on my shoulders, but he was taller than I, and the ground being steep I stumbled, when Captain Campbell climbing up said, “Let me lift him,” and carried him on his shoulder 50 yards down to where the horses were standing in the cattle kraal, under the walls of which the escort were sheltering. I climbed a few yards higher, when a Zulu fired at me from underneath a rock, 20 yards distant. The charge struck my horse immediately in front of the girth, killing it instantaneously, and as it fell, striking my shoulder with its head, knocked me down. I heard an exclamation from my comrades, and scrambling up called, “No, I am not hit!” and as they began climbing the hill, added, “Please stop where you are. I am
  • 39. coming down, for it’s too steep to get on any farther, in this place.” When I got down to the kraal, I saw Mr. Lloyd was dying. He could no longer speak; obtaining some brandy from Lysons, I tried to pour a little down his throat, but his teeth were already set. I told Captain Campbell to order the Irregular horsemen, who were taking cover under rocks below us, to clear the caves from whence the firing had come which killed my horse. He found much difficulty in inducing the men to advance, as they alleged the position was unassailable; and eventually, leading four of my personal escort, with Lieutenant Lysons, he climbed up, Bugler Walkinshaw going with him. I called Walkinshaw back before he was out of sight, for I wanted help for Mr. Lloyd; and thus he, one of the bravest men in the Army, missed the chance of gaining the Victoria Cross. In a few moments one of the men told me that the cave was cleared, but that Ronald Campbell was dead. He had led the small party of three or four men, passing up a narrow passage only 2 feet wide between rocks 12 feet high for several yards, and was looking down into the cave, when a Zulu fired, almost touching him, and he fell dead. Lieutenant Lysons and Private Fowler, 181 90th Light Infantry, undauntedly passing over the body, fired into the cave, and the few Zulus in it disappeared through another opening. By the time the men brought Ronald Campbell’s body down, Mr. Lloyd was dead. Telling Walkinshaw to put his ear down to his heart, he made sure, and then I tried to put the bodies up on my baggage animal. The fire from the rocks on all sides was fairly accurate, killing many out of the 21 ponies we had with us. As bullets were striking all round me on the stones, my pony moved every time I got Campbell’s body on my shoulder. Walkinshaw, who was entirely unconcerned at the bullets, said, “If you will hold it, sir, I will put the bodies up”; and this he did. It then occurred to me that in the wallets of the saddle under my horse, which was lying with all four feet in the air, was Campbell’s wife’s Prayer book, a small one I had borrowed before starting from Kambula, as my own was a large Church Service, and I said to
  • 40. Walkinshaw, “Climb up the hill, and get the prayer book in my wallets; while I do not want you to get shot for the saddle, you are to take all risks for the sake of the prayer book.” He climbed up in a leisurely fashion, and, pulling the saddle from underneath the horse brought it safely down on his head. We then moved down the mountain 300 yards, to find a spot on soil clear of rocks. INHLOBANE, 28th MARCH, 1879 COLONEL EVELYN WOOD TO LORD CHELMSFORD. “MR. LLOYD FELL MORTALLY WOUNDED AT MY SIDE—CAPTAIN CAMPBELL LEADING IN THE MOST GALLANT AND DETERMINED MANNER WAS SHOT DEAD. WE BROUGHT THEIR BODIES HALF-WAY DOWN THE HILL, WHERE WE BURIED THEM, STILL UNDER FIRE”
  • 41. The operation of digging a grave was laborious, as our only implements were the assegais of the native escort, and when it had been completed to about 4 feet in depth, the men got flurried by the approach of some 300 Zulus from the Ityenteka Nek, and, lifting the bodies, placed them in the grave. It was not long enough, and although I realised the possibility of our having trouble with the approaching Zulus, yet as they were still 600 yards off and were most of them bad shots at that range, I had the bodies lifted out, and the grave made a proper length to receive them without the lower limbs being doubled up. When I was satisfied, I read an abridged form of the Burial Service from Mrs. Campbell’s prayer book. We were now assisted by the fire of some of Colonel Buller’s men, who, seeing our difficulty, opened on the advancing Zulus, and, being above them, checked their approach. The officer commanding the Irregulars asked permission to move down the hill to regain Colonel Buller’s track, and by it he finally reached the summit without further casualties. He had lost only 6 men dead, and 7 wounded, up to this hour. As all firing on top of the mountain had now ceased, I decided to move back, and see how the other column had fared. Passing one of the Irregulars who had been shot in the thigh, I put him up on one of the dead men’s horses, and as there was no apparent hurry, Umtonga’s men drove with us a flock of sheep and goats. We stopped occasionally to give the wounded man stimulants, being unconscious that the main Zulu Army was moving on our left, across, and towards our path. When we were under the centre of the mountain, Umtonga, whom I had sent out to a ridge on our danger flank, gesticulated excitedly, explaining by signs that there was a large army near us. Cantering up, I had a good view of the Force, which was marching in 5 columns, with the flanks advanced, and a dense Centre—the normal Zulu attack formation. I sent Lieutenant Lysons to the officer commanding the western party with the following order:— “Below the Inhlobane. 10.30 a.m. 28/3/79.
  • 42. “There is a large army coming this way from the South. Get into position on the Zunguin Nek. E. W.” The plateau which Colonel Buller’s force had cleared was 150 feet higher than the Lower Plateau on which the western column stood, but both parties saw the Zulu Army a considerable time before I did, as I was 1000 feet below them. Buller had seen it at 9 a.m., and the western force had seen it rather earlier, Buller being engaged in covering a party of 25 of the Frontier Light Horse under Captain Barton, Coldstream Guards, who were descending the eastern slope to bury one or two men killed in the assault. Sending word to Captain Barton to retire, Buller fell back to the western end of the mountain, and forming some selected men into a rear guard, he took them down the almost precipitous edge of the Upper Plateau. The path was down the apex of a salient angle, with long sides, and the head of the descent was well suited for defence. Buller’s men had previously collected a great number of cattle, which had been driven down towards the Zunguin Nek at 7 a.m. Colonel Buller and all his party would have got safely away had not the Makulusi, and the men of the Regular regiment with it, taking courage at the advance of the Zulu Army, emerged from their caves and harassed the retreat, during which some valuable lives were lost. Colonel Buller came down, practically the last man, and was at the foot of the descent from the Upper Plateau, when, seeing men nearly surrounded by Zulus, he went back on two occasions, and brought out in succession two on his horse. Piet Uys came down with him, until he saw one of his sons having difficulty with his horse, and, going back, was assegaied by a Zulu crouching behind him. 182 About 80 of the First Battalion of Wood’s Irregulars were overtaken and killed, and with them, to my great regret, Captain Potter, and Lieutenant Williams 183 of the 58th regiment.
  • 43. The main Zulu Army being exhausted by their march, halted near where Vryheid now stands, but some of their mounted men came on, and a few of the more active and younger footmen. Before leaving camp I had given orders for a barricade of planks, 5 feet high, to be erected, and securely bolted into the ground with supporting struts, to run between the redoubt and the south end of the cattle laager, to stop a rush from the ravine on to the fort. To those who objected that the Zulus would charge and knock it down by the weight of their bodies, I replied it would cause a delay of several minutes, during which 300 or 400 rifles, at 250 yards range, ought to make an additional barricade of human bodies, and I now sent an order to the Senior officer in camp, to chain up the waggons, and to continue the strengthening of the barricade. I wrote I had seen between 20,000 and 25,000 Zulus, and remained on the Zunguin Mountain till 7 p.m., hoping to cover the retreat of any more of our men who might come up, being particularly anxious about Captain Barton, 184 of whom we had had no news since he descended the eastern end of the mountain. I never knew until that day the depth of regard which Buller felt for me. I was sitting on the summit of the Zunguin range when he climbed up it, and, seeing me suddenly, uttered so fervent a “Thank God!” that I asked for what he was thankful, and he explained that he thought I had been cut off at the eastern end of the mountain. It rained heavily on the evening of the 28th. All the mounted men had been on the move day and night since the 23rd, when we went to Luneberg; but at 9 p.m., when a straggler came in to say that there were some Europeans coming back by Potter’s Store, Redvers Buller immediately saddled up, and, taking out led horses, brought in 7 men, who were, as we believed, the sole survivors of the parties at the east end of the mountain. So far as I know, the only officer who got down the western end of the Inhlobane on horseback was Major Leet, who commanded the 1st battalion Wood’s Irregulars. Six weeks earlier, at the Athletic Sports, we had a Tug-of-war between the officers of the 13th and
  • 44. 90th Light Infantry, captained by Leet and myself, and as the 90th pulled over the 13th Leet wrenched his knee out of joint, and I had told him to remain in camp on the 27th. This, however, he did not do, and as he could only hobble, he tried, and successfully, to ride down the mountain. I believe he got down before the counter attack; but while on the Lower Plateau, and being followed up closely by the enemy, he showed distinguished courage in going back to help a dismounted officer, for which he received the Victoria Cross. On the night of the 28th March, as I sat at dinner, I could not keep my mind off Ronald Campbell, who had sat opposite me for three months, and had anticipated every want with the utmost devotion, and I cannot write now, even after the lapse of a quarter of a century, without pain of the loss the army sustained when my friend fell. As I visited the outposts at least twice every night from the date of Isandwhana till after Ulandi, 4th July, my clothes were nearly always damp from walking through the long grass, which, when not wet from the heavy rain which fell constantly through the months of February and March, was soaked with dew, and I had forbidden either of the Staff accompanying me, because, as we slept in our boots and clothes, anyone who walked round the sentries got saturated up to the waistbelt. I had, however, once or twice suspected that I was being followed, and one night, turning suddenly in the darkness, I knocked against a man, and then recognised Campbell’s voice, as he answered my challenge. I said sharply, “Why are you disobeying orders? What are you doing here?” “I have always the fear, sir,” he replied, “that one night you won’t hear the challenge of one of the sentries, and you will be shot.” On two occasions on which I was in bed with fever for three days, he nursed me as tenderly as could a woman, and I never saw anyone play a more heroic part than he did on the morning of the 28th March 1879.
  • 47. I CHAPTER XXXI 1879—KAMBULA, 29TH MARCH Mist delays the advance of 23,000 Zulus—Piet Uys having fallen, Burghers leave us—The position under the Ngaba-ka-Hawane—Bigge—Nicholson—Slade— Buller teases Zulu Right Wing into a premature attack—I shoot three Zulu leaders in five successive shots—Hackett’s Counter attack—His wound—His character—Death of Arthur Bright—I recommend Buller for the Victoria Cross. WENT round the sentries twice during the night, although I did not anticipate an attack until daylight, feeling sure the large masses of Zulus I had seen could not make a combined movement in the dark. When the night was past, the mist was so thick that we could not see more than a hundred yards. Captain Maude, who had temporarily replaced Ronald Campbell, asked me if the wood-cutting party of two companies was to go out as usual. Our practice was that they should not start till the front was reported clear for 10 miles, but until the sun came out there was no chance of the mist clearing off, and after thinking over the matter I decided the party should go, because we had never been able to get up reserve of fuel, and it was possible the Zulus might not attack that day. Our men would certainly fight better in two or three days’ time if they had cooked food, and so I accepted the risk, but ordered two subalterns to keep ponies saddled to recall the companies in good
  • 48. time. Fortunately, though 5 miles away, the place was behind the camp. All the mounted men had been continuously in the saddle since daylight on the 23rd, and it was difficult to get a trot out of the horses; 188 but Commandant Raaf went out with 20 men to the edge of the Zunguin plateau, and when the mist lifted, about 10 a.m., reported the Zulu Army was cooking on the Umvolosi and a tributary stream. 189 He remained out himself to warn me when they advanced. All our arrangements in camp were perfected, with the exception of the barricade, to which we had added some strengthening pieces. The Dutchmen came to see me early in the day, to say that, as Piet Uys was dead they wished to go home, and, except half a dozen who had hired waggons to us, they departed. Great pressure had been brought on my gallant friend Piet to induce him to withdraw from the column. His friends told him he was a traitor to their cause, but Uys always replied that although he disliked our policy, he thought it was the duty of a White man to stand up with those who were fighting the Zulus. 190 Between 80 and 100 of Uhamu’s men, who held on to the cattle they had driven from the Inhlobane, were overtaken and killed near the Zunguin Mountain on the 28th, but in the battalion which had gone out with Colonel Buller there were very few casualties. Nevertheless, Zulu-like after a reverse, the two battalions of Wood’s Irregulars, about 2000 strong, dispersed. I spent the forenoon, after saying good-bye to the Uys detachment, in writing a report on the previous day’s reconnaissance, and letters to the bereaved relatives of those who had fallen. At 11 o’clock Raaf reported that the Zulu Army was advancing, and I sent the officers to recall the wood-cutting parties, and had all the Trek oxen driven in, except about 200 which had strayed away
  • 49. from the drivers, whose duty it was to herd them. We got the two companies back in time for the men to have a hasty dinner before the attack actually began. The commanding officers asked if the battalions might not be told to hurry their dinners, but I said, “No; there is plenty of time,” for by the system enforced in the column during daylight, as Lord Chelmsford saw five weeks later, our tents could be struck, and the men be in position in the laager, within seventy seconds from the last sound of the “Alert.” At 1.30 p.m. Colonel Buller suggested he should go out and harry the Zulus into a premature attack, and this he did admirably. We had shifted camp several times for sanitary reasons. My friends the Dutchmen could never be persuaded to use the latrines, although I had one dug specially for them; moreover, Wood’s Irregulars and the oxen had so fouled the ground as to induce fever, unless the camp was often shifted. The position in which we received the attack was on a ridge running in a south-westerly direction, an under feature of the Ngaba-ka-Hwane Mountain. The waggons of the 13th Light Infantry formed the right front and flank, 4 guns were in front of the centre, and the 90th Light Infantry on the left. The Horse Lines were in the middle, and the rear face of the Laager was held by the Irregular Horse; 280 yards in front, on ground 20 feet higher than the Laager, was a redoubt, its main lines of fire being in a northerly and southerly direction, while 150 yards to the right front of the main Laager was a cattle Laager, into which we crammed upwards of 2000 oxen. The outer side of it stood on the edge of a deep ravine, into which the Laager drained. The wheels of the waggons were securely chained together, and the space between the forepart of one and the rear of the other was rendered difficult of ingress by the poles (or dyssel-booms), being lashed across the intervals. Two guns under Lieutenant Nicholson were placed en barbette, 191 at the front end of the Redoubt. The other four guns came into action under Lieutenant A. Bigge 192 and Lieutenant
  • 50. Slade, 193 by sections on the ridge, connecting the Redoubt with the main Laager. The men belonged to Garrison Companies, but I have never known a battery so exceptionally fortunate in its Subalterns. Lieutenant Nicholson, standing on the gun platform, fought his guns with the unmoved stoical courage habitual to his nature. Major Tremlett was renowned as a fearless sportsman, and both Bigge and Slade were unsurpassable; they with their gunners stood up in the open from 1.30 p.m. till the Zulus retreated at 5.30 p.m., and by utilising the ridge were enabled to find excellent targets with cover during the first attack on the southern slope, and later on the northern slope, and suffered but little loss. The direction of the Zulu advance was, speaking generally, from south-east, but when they came in sight they stretched over the horizon from north-east to south-west, covering all approaches from the Inhlobane to Bemba’s Kop. When still 3 miles distant, 5000 men moved round to our Left and attacked the side held by the 90th Light Infantry, prior to the remainder of the Zulu Army coming into action. This fortunate circumstance was due to Colonel Buller’s skilful tactical handling of the mounted men, whom he took out and dismounted half a mile from the Zulus. The Umbonambi regiment suffered a galling fire for some time, and then, losing patience, rushed forward to attack, when the horsemen, remounting, retired 400 yards, and, repeating their tactics, eventually brought on a determined attack from the Zulu right flank. The Umbonambi followed up the horsemen until they were within 300 yards of the Laager, when their further advance was checked by the accurate firing of the 90th Light Infantry, greatly assisted by the enfilading fire poured in from the northern face of the Redoubt. I saw a fine tall Chief running on well in front of his men, until, hit in the leg, he fell to the ground. Two men endeavoured to help him back as he limped on one foot. One was immediately shot, but was replaced by another, and eventually all three were killed. We now sent the Artillery horses back into the Laager, keeping the guns in the open, on the ridge between the Redoubt and the
  • 51. main Laager. I had instructed the officer commanding to serve his guns till the last moment, and then, if necessary, leaving them in the open, take his men back to the Laager, which was within 188 yards. The attack on our Left had so slackened as to give me no further anxiety, when at 2.15 p.m. heavy masses attacked our Right Front and Right Rear, having passed under cover up the deep ravine, on the edge of which the cattle Laager stood. Some 40 Zulus, using Martini-Henry rifles which they had taken at Isandwhlana, occupied ground between the edge of the ravine and the rear of the Laager, from the fire of which they were partly covered by the refuse from the Horse Lines which had been there deposited, for, with the extraordinary fertility of South Africa, induced by copious rains and burning midday sun, a patch of mealies 4 feet high afforded cover to men lying down, and it was from thence that our serious losses occurred somewhat later. The Zulu fire induced me to withdraw a company of the 13th, posted at the right rear of the cattle Laager, although the front was held by another half company for some time longer. I could see from where I stood on the ridge of land just outside the fort, leaning against the barricade, which reached down to the cattle Laager, that there were large bodies in the ravine, the Ngobamakosi in front, and 30 men (leaders) showed over the edge, endeavouring to encourage the Regiment to leave the shelter, and charge. I, in consequence, sent Captain Maude to order out two companies of the 90th, under Major Hackett, with instructions to double over the slope down to the ravine with fixed bayonets, and to fall back at once when they had driven the Zulus below the crest. A 13th man coming away late from the cattle Laager, not having heard the order to retire, was shot by the Zulus lying in the refuse heap, and followed by four from the cattle Laager. I was running out to pick him up, when Captain Maude exclaimed, “Really it isn’t your place to pick up single men,” and went out himself, followed by Lieutenants Lysons and Smith, 90th Light Infantry; they were bringing the man in, who was shot in the leg, when, as they were
  • 52. raising the stretcher, Smith was shot through the arm. I was firing at the time at a leader of the Ngobamakosi, who, with a red flag, was urging his comrades to come up out of the ravine, and assault the Laager. Private Fowler, one of my personal escort, who was lying in the ditch of the fort, had asked me, “Would you kindly take a shot at that Chief, sir? it’s a quarter of an hour I am shooting him, and cannot hit him at all.” He handed me his Swinburne-Henry carbine, and looking at the sight, which was at 250 yards, I threw the rifle into my shoulder, and as I pressed it into the hollow, the barrel being very hot, I pulled the trigger before I was ready,—indeed, as I was bringing up the muzzle from the Zulu’s feet. Hit in the pit of the stomach, he fell over backwards: another leader at once took his place, cheering his comrades on. At him I was obliged to fire, unpleasantly close to the line of our officers leading the counter attack. I saw the bullet strike some few yards over the man’s shoulder, and, laying the carbine next time at the Zulu’s feet, the bullet struck him on the breastbone. As he reeled lifeless backward, another leader seized and waved the flag, but he knelt only, though he continued to cheer. The fourth shot struck the ground just over his shoulder, and then, thinking the carbine was over-sighted, 194 I aimed on the ground 2 yards short, and the fifth bullet struck him on the chest in the same place as his predecessor had been hit. This and the counter attack so damped the ardour of the leaders that no further attempt was made in that direction, although several brave charges were made to the south of the cattle Laager, against the right flank of the Redoubt. While I was firing at the leaders of the Ngobamakosi Regiment, who, from the ground falling away towards the ravine, were out of sight of the main Laager, the two companies 90th Light Infantry came out at a steady “Double,” Major Hackett leading, guided by Captain Woodgate, who knew exactly where I wished the companies to go, and how far the offensive movement was to be carried out. Lieutenant Strong, who had recently joined us, ran well in front of his company, sword in hand, and the Zulus retired into the ravine. The companies, however, were fired on heavily from the refuse heaps, at 350 yards range, and Major
  • 53. Hackett was shot through the head; Arthur Bright fell mortally wounded, and the Colour-Sergeant of Bright’s company, Allen, a clever young man, not twenty-three years of age, who had been wounded in the first attack, and, having had his arm dressed, rejoined his company as it charged, was killed. The Umcityu and Unkandampenvu had charged so determinedly over the open on our Left front, as had part of the Ngobamakosi up the slope to the Redoubt, from the south side of the cattle Laager, that I did not at first realise the full effect of Hackett’s counter attack, and apprehended the mass still crouching below the crest would rush the Right face of the Laager. They would have had some 200 yards to pass over from the edge of the ravine to the waggons, but, owing to the ground falling rapidly, would have been under fire from the Laager for 100 yards only. I therefore went into the main Laager, being met by Colonel Buller, who asked me cheerily for what I had come, and I replied, “Because I think you are just going to have a rough and tumble”; but Hackett’s charge had done even more than I had hoped, and having looked round I went back to my position just outside the fort. At 5.30 p.m., when the vigour of the attack was lessening, I sent Captain Thurlow and Waddy’s companies of the 13th Light Infantry to the right rear of the cattle Laager, to turn out some Zulus who were amongst the oxen, which they had, however, been unable to remove; and I took Captain Laye’s 195 company to the edge of the krantz on the right front of the Laager, where they did great execution with the bayonet amongst the Undi Regiment, who were now falling back. I then sent a note to Buller, asking him to take out the mounted men, which he did, pursuing from 5.30 p.m. till dark, and killing, as it happened, chiefly the Makulusi tribe, who had been his foes on the previous day. When the enemy fell back in the direction in which they had come, they were so thick as to blot out all signs of grass on the hillside, which was covered by their black bodies, and for perhaps
  • 54. the only time in anyone’s experience it was sound to say, “Don’t wait to aim, fire into the black of them.” At 3 a.m. on the 30th, one or two shots from the Outpost line roused the camp, and the Colonial corps opened a rapid fire to the Front, immediately over the heads of the two line battalions and artillery, who stood perfectly steady. Rain was falling, so, while Maude was ascertaining the cause of the firing, which was a Zulu who, having concealed himself till then, jumped up close to one of our sentries, I sat in an ambulance near the battery until the Colonials having put three bullets into the top of it, I thought it would be better to get wet than be shot by our own men. After five minutes the firing was stopped. The scare was excusable, for the nerves of the mounted men had been highly strung for some hours, a fourth of those who had ridden up the Inhlobane having been killed. In the next few days we buried 785 men within 300 yards of our Laager, which we were afterwards obliged to shift on account of the number of bodies which lay unseen in the hollows. We learnt after the battle that when the Zulus saw our tents go down they thought it was in preparation for flight, and that unsteadied their Right Wing. 196 They never fought again with the same vigour and determination. The Line battalions were very steady, expending in four hours on an average 33 rounds a man; though that evening I heard that some of them had thought the possibility of resisting such overwhelming numbers of brave savages, 13 or 14 to one man, was more than doubtful. I had no doubt, and lost all sense of personal danger, except momentarily, when, as on five occasions, a plank of the hoarding on which I leant was struck. This jarred my head, and reminded me that the Zulus firing from the refuse heap in the right rear of the Laager were fair shots. A few had been employed as hunters, and understood the use of the Martini rifles taken at Isandwhana.
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