Intel Edison: Beyond the Breadboard
- 1. Intel Edison: Beyond the breadboard 1 By: Yeo Kheng Meng (yeokm1@gmail.com)Hackware v1.9 (29 June 2016)
- 2. Why beyond the breadboard? 2 One of Algoaccess’s hardware product
- 3. 3 Algo Access’s hardware setup OD, OS, CYL… OD, OS, CYL… Direct or USB-Ethernet adapter RS232 DB-9 Serial port
- 4. Agenda 1. Intel Edison Basics 2. Hardware experience 3. Software experience 4
- 5. So what is the Intel Edison? 5 35.5mm x 25 mm x 3.9mm System-on-module (SOM) • Using Hirose 70-pin DF40 Series Connector (0.4mm pitch)
- 6. Raspberry Pi 3 vs Intel Edison specifications 6 Specifications Raspberry Pi 3 Intel Edison CPU 1.2Ghz quad-core BCM2837 Cortex-A53 ARMv8 (64-bit) 500Mhz dual-core Intel Atom x86 (32-bit) + Intel Quark MCU GPU 400Mhz Videocore IV None RAM 1GB DDR2 1GB DDR3 Storage External microSD cad 4GB eMMC flash onboard Networking Single band 802.11n Wifi + Dual-mode BT + LAN Dual-band 802.11n Wifi + Dual-mode BT I/0 Connectivity 3.3V level level GPIO bank + connectors 1.8V logic level GPIO-bank Price US$35 US$50++ Power consumption (Idle/Peak) 1W/3.6W 0.1W / 1 W Dimensions 85 x 56 x 17mm 35.5 x 25 x 3.9mm
- 7. 2 models of Intel Edison 7 No chip antenna image from: http://www.nix.ru/autocatalog/thin_clients/208148_2254_draft_large.jpg From Intel Edison Compute Module Hardware Guide (June 2016) Page 13 http://www.intel.com/content/www/us/en/support/boards-and-kits/000005808.html
- 8. Official Intel carrier boards 8 Mini Breakout board • USB Serial • USB-OTG • GPIO pins (1.8V logic level) • ~US$25 Arduino Breakout board • Arduino-style pins • USB-Serial • USB-OTG • Micro-SD slot • DC Jack 7-15V DC • 3.3V or 5V logic levels depending on J9 position • Default is 5V • ~US$60 https://www.arduino.cc/en/ArduinoCertified/IntelEdison
- 9. Sparkfun stackable/carrier boards 9 Base Block 64x48 0.66” OLED + buttons “Level-shiftable” GPIO breakout 9-DOF IMU Dual H bridge Battery board
- 10. Prototyping: Bare breakout board 10 • Hirose 70-pin DF40 Series Receptacle Connector (0.4mm pitch) • Tough to solder by hand without magnifying glass/microscope • Stencil highly recommended to avoid solder bridges • https://github.com/algoaccess/intel-edison-pin-breakout
- 11. Hirose 70-pin DF40 interface 11 Pin Function Description 1, 5, 9, 11, 13, 15 GND Ground 2, 4, 6 VSYS in Power Input (3.3V to 4.5V) 14 DCIN Connect to VSYS if powered from external power 8, 10, 12 3.3V/1.8V out Reference voltage (100mA) 46, 61, 63, 65 UART1 (with flow control) UART with flow control /dev/ttyMFD1 22, 27 UART2 (no flow control) Linux debug serial port /dev/ttyMFD2 3, 16, 18, 20 USB (USB_VBUS does not supply power) USB interface 41, 43 45, 47 I2C1 I2C6 2x I2C interfaces Only master supported 51, 53, 55, 57, 59 SPI Master/Slave supported Chip select: 51, 53 Picture from: https://learn.sparkfun.com/tutorials/general-guide-to-sparkfun-blocks-for-intel-edison All pins except power and USB operate at 1.8V levels
- 12. 1.8V logic levels • All pins except power and USB operate at 1.8V levels • But most chips are using 3.3/5.0 V • For eg, MAX3232 RS232-TTL transceiver (3.3V) • Use a level shifter like TXS0108EPWR • Reference 1.8V from Module Pin 12 • For LEDs, you can just use a transistor 12
- 13. Bug: Using GPIO48 destabilises Wifi 13 http://iotdk.intel.com/docs/master/mraa/edison.html Arduino Pin 7 can sometimes negatively impact the WiFi capability, if using WiFi avoid using this pin Pin Naming Aliases: GP48 Compute Module Pin 32 Arduino Pin 7
- 14. Avoid GPIO48 14J19, Pin 6
- 15. USB On-The-Go 15Adapted from Intel Edison Compute Module Hardware Guide (June 2016) Page 36 http://www.intel.com/content/www/us/en/support/boards-and-kits/000005808.html • Host mode • Connect USB peripherals like flash drives • Client mode • Loading firmware (DFU mode) • USB OTG supports both Host and Client • Can use a Double pole, double throw (DPDT) switches USB Role USB_ID (Pin 3) FAULT (Pin 19) USB_VBUS (Pin 20) Host GND Floating Floating Client Floating GND Host 5V GND Fault USB_ID USB-A Power Line USB_VBUS Source 5V Client Host
- 16. Intel Edison Linux Distributions 1. 1.6 (Default) • Based on “Poky” Linux distribution • Compile Poky Linux sources/packages using provided toolchain and recipes • Limited “opkg” package manager and few default packages • (eg, no nano, only vi) • Can add third party “meta-openembedded” recipes during compile time 2. • Produced by Emutex Labs • Based on Debian 7 Wheezy (2013) • More packages compared to Yocto using (apt-get) • Packages outdated compared to Debian 8 Jessie (2015) 3. Compile your own: Yocto or Debian Jessie • All use old kernel version 3.10.17 (Oct 2013) 16
- 17. Poor default support for USB-Ethernet and USB-Serial adapters • Only supports adapters based on these chipsets • Ethernet: ASIX AX88xxx USB 2.0 to Gigabit adapter • Serial: Prolific PL2303 USB-Serial adapter • More support requires kernel recompilation 17
- 18. Small rootfs partition size 18 • 1.4GB, 541MB available on initial boot, may be too small for some uses • Modifying rootfs partition size requires recompilation
- 19. My compilation script • Compiles in all available USB-Ethernet/Serial drivers, custom rootfs size • Downloads sources, modifies compile options then compile • https://github.com/algoaccess/edison_mod_kernel_image_gen 19
- 20. Lengthy compilation time • 4-6 hours typical • Use the cloud -> Google Compute Engine or AWS (About half hour on 32 threads) • export SETUP_ARGS="--parallel_make=32 --bb_number_thread=32" • IMPORTANT: Remember to SHUT DOWN your instance once finished, if not hefty charges will be incurred!!! 20
- 21. File System safety for embedded systems • Improper shutdown of systems can corrupt file systems • Cause: System off while data is being written 1. Read-only file system • No writes to file-system allowed, no chance of system corruption 2. Enable full-journaling • File-system journals store a list of changes to be made • Ext4 default is to journal meta-data only, not the data itself • We should also journal the data for additional protection 21
- 22. Read-only file system (preferred) • ----------------/etc/fstab------------------------ rootfs / auto ro 1 1 /dev/disk/by-partlabel/boot /boot auto ro 1 1 /dev/disk/by-partlabel/home /home auto ro 0 2 tmpfs /var/tmp tmpfs nodev,nosuid 0 0 tmpfs /var/log tmpfs nodev,nosuid 0 0 • ------------------------------------------------------ • tmpfs: RAM drive • nodev,nosuid: Security precautions for world-writeable file-systems 22https://gist.github.com/yeokm1/00bf00fbcda99cc33c2b
- 23. Mount file system to journal everything • Set journal option to / partition • tune2fs -o journal_data /dev/mmcblk0p8 • Set journal option to /home partition • tune2fs -o journal_data /dev/mmcblk0p10 • ----------------/etc/fstab------------------------ • rootfs / ext4 data=journal,sync,noatime 1 1 • /dev/disk/by-partlabel/boot /boot auto ro 1 1 • /dev/disk/by-partlabel/home /home ext4 data=journal,sync,noatime 0 2 • ------------------------------------------------------ • data=journal: Journal everything. Data will be written twice, first in to journal, second into disk • sync: Commit changes to disk immediately, do not cache. Performance loss • noatime: Do not store last access time to increase disk performance to avoid updating access time in every sync 23
- 24. QnA 24