Toolchain » History » Version 5
laforge, 02/28/2016 06:47 PM
| 1 | 1 | laforge | |
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| 3 | 4 | steve-m | h1. Toolchain for firmware builds |
| 4 | 1 | laforge | |
| 5 | 4 | steve-m | |
| 6 | The SAM3U microcontroller used in [[OsmoSDR]] is based on an ARM Cortex-M3 core. |
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| 8 | 2 | laforge | Cortex-M differs from classic ARM (ARM7TDMI) in a number of ways. One of them is that it only supports |
| 9 | the Thumb2 instruction set, and neither the 32-bit ARM nor the older Thumb instruction set. |
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| 11 | This means that any code compiled for it needs to be pure Thumb2, with no ARM interworking. The best way |
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| 12 | 1 | laforge | to ensure this is to create a separate toolchain for it. |
| 13 | 2 | laforge | |
| 14 | 1 | laforge | As an example, you can follow the instructions from |
| 15 | 4 | steve-m | * http://openmulticopter.org/wiki/Building_an_ARM_Cortex-M3_toolchain |
| 16 | 1 | laforge | |
| 17 | 3 | steve-m | where you will have to run the summon-arm-toolchain script with: |
| 18 | 4 | steve-m | <pre> |
| 19 | 3 | steve-m | ./summon-arm-toolchain TARGET=arm-cm3-eabi DEFAULT_TO_CORTEX_M3=1 |
| 20 | 4 | steve-m | </pre> |
| 21 | 1 | laforge | |
| 22 | 3 | steve-m | to generate the toolchain. It will download all required components/dependencies |
| 23 | 2 | laforge | as a first step of the compilation process. |
