Stm32cube framework - How to build with proper CMSIS DSP library

[jaishankar]

Question

In PlatformIO STM32F103 uses the framework stm32cubef1, which has many driver and not all of them are consider during compile by the PlatformIO.

For Example I want to enable driver required for CMSIS DSP,

• then libarm_cortexM3l_math.a is required, which is already present in ...\framework-stm32cubef1\Drivers\CMSIS\Lib\GCC
• How enable or link this driver while compile? and what is correct way?

Current Work around[Working Good]

Step 1:

Copied the file libarm_cortexM3l_math.a from location ...\framework-stm32cubef1\Drivers\CMSIS\Lib\GCC into ..\lib\cmsis

Step 2:

In platformio.ini file

[env:bluepill_f103c8_128k]
platform = ststm32
board = bluepill_f103c8_128k
framework = stm32cube
upload_protocol = cmsis-dap
debug_tool = cmsis-dap
build_flags = 
    -D ARM_MATH_CM3 ; Required for CMSIS-DSP library(arm_math.h)
    -L lib/cmsis   ; add the directory where libarm_cortexM3l_math.a is located
    -l libarm_cortexM3l_math      ; instruct the linker to link this library

Step 3:

In ‘main.c’ file,

......
......
#include "arm_math.h"
int16_t data_set[] = {1234, 5678, 9876, 4321, 3456, 7890, 6543, 2109, 8765, 1234, 5678, 9012, 2345, 6789, 4321, 8765, 1098, 3456, 7890, 6543};
int16_t array_size = 19;
......
......
int main(void)
{
......
......
    int16_t _max_cmsis = 0;
    uint32_t _max_cmsis_index = -1;
    int16_t _min_cmsis = 0;
    uint32_t _min_cmsis_index = -1;
    arm_max_q15(data_set, array_size, &_max_cmsis, &_max_cmsis_index);
    arm_min_q15(data_set, array_size, &_min_cmsis, &_min_cmsis_index);
......
......
}
......
......

Other Case

Mentioned to download from CMSIS Version 5 library, which is no longer maintained. Arm moved to different repo named as CMSIS-DSP

Stm32cube framework - fail to build CMSIS DSP sources

https://github.com/speedcontrols/dc_sc_grinder/tree/dev (dev branch) I tryed to use rfft functions from CMSIS DSP (comes with stm32cobe framework). But got linker errors like undefined reference to 'arm_rfft_init_q31'. Also tried -l arm_cortexM0l_math, but not succeeded too. https://github.com/speedcontrols/dc_sc_grinder/blob/dev/src/meter.cpp - that’s a concrete file, calling rfft. Could you help me how to build CMSIS DSP from embedded sources? (i’d prefer to not link pre-build library, bec…

[maxgerhardt]

@jaishankar

Step 1:

Copied the file libarm_cortexM3l_math.a from location ...\framework-stm32cubef1\Drivers\CMSIS\Lib\GCC into ..\lib\cmsis

You don’t need to do that at all. As documented, unless you set board_build.stm32cube.custom_dsp_library = yes in the platformio.ini, then the STM32Cube builder script will automatically find the path to CMSIS-DSP as it’s inside framework-stm32cubef1 and add it to the 1. includepath and 2. library include path.

However, it doesn’t yet link the library or define the right ARM_MATH_CMxxx macro.

Still, without copying any file, we can write

[env:bluepill_f103c8_128k]
platform = ststm32
board = bluepill_f103c8_128k
framework = stm32cube
build_flags = 
  -DARM_MATH_CM3
  -larm_cortexM3l_math

And that will use the libarm_cortexM3l_math.a from framework-stm32cubef1. (Note: When specfying to link a library with -l <library name>, that library name should be without the lib prefix. PlatformIO fixes up this common mistake silently though.)

So, this will compile without any problems

#include "stm32f1xx.h"
#include "arm_math.h"
int16_t data_set[] = {1234, 5678, 9876, 4321, 3456, 7890, 6543, 2109, 8765, 1234, 5678, 9012, 2345, 6789, 4321, 8765, 1098, 3456, 7890, 6543};
int16_t array_size = 19;

int main() {
    int16_t _max_cmsis = 0;
    uint32_t _max_cmsis_index = -1;
    int16_t _min_cmsis = 0;
    uint32_t _min_cmsis_index = -1;
    arm_max_q15(data_set, array_size, &_max_cmsis, &_max_cmsis_index);
    arm_min_q15(data_set, array_size, &_min_cmsis, &_min_cmsis_index);
    return 0;
}

Conversely, if you do have a custom-compiled CMSIS-DSP library, that is both header and library file, then you can add it like

[env:bluepill_f103c8_128k]
platform = ststm32
board = bluepill_f103c8_128k
framework = stm32cube
; DISABLE INTERNAL CMSIS-DSP LIBRARY
board_build.stm32cube.custom_dsp_library = yes
build_flags = 
    -D ARM_MATH_CM3 ; Required for CMSIS-DSP library(arm_math.h)
    ; assumes -I lib/cmsis is automatically present thanks to library structure
    -L lib/cmsis   ; add the directory where libarm_cortexM3l_math.a is located
    -l arm_cortexM3l_math      ; instruct the linker to link this library

[jaishankar]

Understand
Thanks for the detailed explanation @maxgerhardt