C++ for Marine Streamer Positioning and Navigation - ACCU 2011
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This document discusses C++ development for marine streamer positioning and navigation. It covers Western Geco's seismic acquisition technologies and services. It then discusses the technical challenges of high data volume and power constraints for physically long streamers. The document proposes using C++ on resource-constrained embedded systems by building a custom GCC toolchain and employing techniques like disabling exceptions and RTTI, limiting standard library usage, and using a custom heap allocator. It emphasizes the benefits of vendor independence and full source code control.
C++ for Marine Streamer Positioning and Navigation - ACCU 2011
- 1. C++ for Marine Streamer Positioning & Navigation Mike Long Schlumberger Western Geco
- 2. Our Technologies and Services Schlumberger Information Western Geco Solutions Drilling & Measurements Data & Consulting Services Reservoir Management Reservoir Characterization Integrated Project Wireline Management Reservoir Production Artificial Lift Well Testing Completions Well Services
- 3. Western Geco : Seismic acquistion You Tube - marine seismic acquisition
- 5. Streamer Navigation & Positioning
- 6. Western Geco : Technical Challenges Data Volume Tens of thousands of sensors acquiring real time data (+ranging and status) Power Physically long streamers Cost Proprietary hardware systems Custom chip development
- 7. C++ On a Shoestring Building a gcc cross compile toolchain for the Stellaris LM3S8962 Cortex-M3
- 8. Topics What is a toolchain and how to choose one? Building your own gcc cross compile toolchain. Stacks & Heaps: Linker Scripts Programming and On-chip debugging The time before "int main()" C++ on a diet Testable Embedded C++
- 9. What makes up a toolchain?
- 10. What makes up a toolchain
- 11. What makes up a toolchain
- 12. How to choose a toolchain Step 0, surveying the options: Are there any options? Paid or Free? Are you paying for the compiler or for support? Does the compiler require a license? Step 1: what is the lifetime of the product/target? Projects with a limited shelf life don't need to be too concerned about source availability Extended life products will benefit from source availability
- 13. How to choose a toolchain Given that we make long-lived products, source availability is desirable. So: are there any companies providing toolchains?
- 14. How to choose a toolchain Given that we make long-lived products, source availability is desirable. So: are there any companies providing toolchains?
- 15. How to choose a toolchain Given that we make long-lived products, source availability is desirable. So: are there any companies providing toolchains? + Up and running quickly + Tested and supported - Proprietary startup code and libraries - Licence management
- 16. How to choose a toolchain Build from source: Some companies provide a "lite" gcc toolchain for free with full source. Some popular targets already have a gcc cross compiler out of the box. If you are really lucky it might even be part of your distribution: #sudo apt-get install gcc-arm-linux-gnueabi qemu-kvm-extras If you are particularly masochistic you can build each component from the sources and independently verify each component and the dependencies (not for the faint of heart). Or you can use a toolchain builder (like crosstool-NG)
- 17. How to choose a toolchain
- 18. Crosstool-NG crosstool-NG is a tool to build cross-toolchains Kernel-like menuconfig interface Large number of supported architectures uClibc-, glibc- or eglibc-based toolchain supported Can create toolchains that target linux and bare-metal Supports both soft- and hard- float toolchains Debug facilities (native and cross gdb, gdbserver) Watch out though, the default configuration for cortex- m3 doesn't enable gdb. Remember to adjust the config!
- 19. Crosstool-NG #install crosstool-ng bzip2 -d crosstool-ng-1.8.1.tar.bz2 tar -xf crosstool-ng-1.8.1.tar cd crosstool-ng-1.8.1/ sudo apt-get install awk sudo apt-get install gawk sudo apt-get install bison sudo apt-get install flex sudo apt-get install automake sudo apt-get install libtool sudo apt-get install libncurses-dev sudo apt-get install zlib1g-dev ./configure make sudo make install mkdir /home/user1/arm-eabi/ cd /home/user1/arm-eabi/ #copy sample file for baremetal build to new directory cp /home/user1/downloads/crosstool-ng-1.8.1/samples/arm-bare_newlib_cortex_m3_nommu- eabi/crosstool.config .config #build the entire toolchain ct-ng build
- 20. Crosstool-NG Kernel-like menuconfig interface Large number of supported architectures uClibc-, glibc- or eglibc-based toolchain supported Can create toolchains that target linux and bare-metal Supports both soft- and hard- float toolchains Debug facilities (native and cross gdb, gdbserver) Watch out though, the default configuration for cortex- m3 doesn't enable gdb. Remember to adjust the config!
- 21. Stacks & Heaps: Linker Scripts
- 22. Stacks & Heaps: Linker Scripts Gcc uses a linker script to decide what goes where, and when:
- 23. Stacks & Heaps: Linker Scripts
- 24. Stacks & Heaps: Linker Scripts
- 25. Stacks & Heaps: Linker Scripts
- 26. Stacks & Heaps: Linker Scripts
- 27. From link-time to run-time: Programming and On-chip debugging
- 28. The time before "int main()"
- 29. The time before "int main()"
- 30. The time before "int main()"
- 31. C++ on a diet
- 32. C++ on a diet The standard C and C++ runtime has many code and data greedy features. How to shave off some of the bloat? Minimize standard library use? Disable exceptions? Restrict dynamic memory allocation? Custom heap allocator? Disable runtime type identification?
- 33. C++ on a diet -fno-rtti -fno-exceptions -nostdlib -nostartfiles -Xlinker --no-gc-sections
- 34. C++ on a diet
- 35. C++ on a diet
- 36. C++ on a diet
- 38. Testable Embedded C++: HIL
- 39. Conclusions Why would anyone do this? Time consuming Difficult to estimate Hard
- 40. Conclusions Why would anyone do this? Why would anyone do this? Time consuming Vendor Independence Difficult to estimate Full source Hard No "magic" Fully configurable Great learning experience
- 42. Credits OpenOCD https://sites.google.com/a/stf12.net/developer-sw-fw/eclipse-demo Choose You: http://www.flickr.com/photos/buzzbishop/3270420690/ Fish Stack: http://www.flickr.com/photos/14903992@N08/4053566319/in/photostream/ Fish Heap http://www.flickr.com/photos/bansal98/2389487868/ Burger http://www.flickr.com/photos/derusha/561781801/ Salad http://www.flickr.com/photos/freddy/39340695/ Go the right way: http://www.flickr.com/photos/elenahneshcuetphotography/4438510791/