ARM DSP with STM32f334c8

[ASSAAD.ASSAAD]

Posted on November 11, 2015 at 12:20

Hello ;

I have a problem for the last few days it made be puzzled hope you could help me please . I am using keil compiler with STM32f334c8 ; I had a project based on stm32f429 using FFT from ARM DSP library ; there is a file arm_common_tables.c generate a code size of about 38kbye ; when I move to a new project based on STM32f334c8 the generated code is 160kbyte ! What I am missing here , any I dea please ?

arm_status status; 
float32_t maxValue; 
arm_cfft_radix4_instance_f32 S; 
//status = ARM_MATH_SUCCESS; 
/* Initialize the CFFT/CIFFT module */ 
status = arm_cfft_radix4_init_f32(&S, fftSize, 
ifftFlag, doBitReverse); 
/* Process the data through the CFFT/CIFFT module */ 
arm_cfft_radix4_f32(&S, testInput_f32_10khz); 
/* Process the data through the Complex Magnitude Module for 
calculating the magnitude at each bin */ 
arm_cmplx_mag_f32(testInput_f32_10khz, testOutput, 
fftSize); 
/* Calculates maxValue and returns corresponding BIN value */ 
arm_max_f32(testOutput, fftSize, &maxValue, &testIndex); 

I am using these code in too diffirent project ; but I get RO size diffirent . Thank you inadvanced

[AvaTar]

Posted on November 11, 2015 at 14:58

I don't think it has to do with the arm_common_tables.h file.

If I remember correctly, the CFFT example you are referring to (coming with the DSP Lib code), has it's ''input signal'' hardcoded as ''const'' data in a separate file. To confirm this, find out where the

testInput_f32_10khz[]

array is defined (not declared !). In your application, it will probably end up in the code section (i.e. Flash). Check the MAP file where this array is located - or if you have replaced it. In addition, check that your F334 project uses the FPU (build option ''-mfloat-abi'' is either ''softfp'' or ''hard''). Option ''soft'' (no FPU) will pull in additional emulation code. And of course, have equivalent optimisation settings in both projects.

[Tesla DeLorean]

Posted on November 11, 2015 at 15:15

I'm not sure Keil has the same soft/hard distinction, things are build with ''Use FPU'' or not.

I'd double check you're using the same version of the CMSIS library, and the defines passed into the compiler.__TARGET_CPU_CORTEX_M4_FP 1ARM_MATH_CM4 1ARM_MATH_MATRIX_CHECK 1ARM_MATH_ROUNDING 1__FPU_PRESENT 1And pulling in the right library file.STM32F30x_DSP_StdPeriph_Lib_VX.X.X\Libraries\CMSIS\Lib\ARM\arm_cortexM4lf_math.lib

[AvaTar]

Posted on November 11, 2015 at 16:22

You are probably right. However, I don't have/use Keil, so I leave it to the O.P. to check those settings.

I guess for the price of this toolchain, on can expect a builtin ''single-click GUI solution'' to switch between FPU and emulation ...

[ASSAAD.ASSAAD]

Posted on November 15, 2015 at 11:33 Thank you all ; I will try it .