TMS320F28069: How use sine and cos math tables in boot rom

Damith Pavithra

Part Number: TMS320F28069
Other Parts Discussed in Thread: C2000WARE

Hi

Where can i find a complete guide of how use boot rom sine and cosine math tables (NOT IQ MATH) in my code, instead of C sinf library function.
Will this create a significant performance improvement?

Thank you

over 2 years ago

0 Sira Rao80 over 2 years ago

TI__Mastermind 26000 points

If you're using the F28069, it has an FPU, but no TMU. With the TMU, you would've been able to use its Hardware instructions for sin and cos instead of the library function. Without the TMU, but with the FPU, you can use the FPUFastRTS library provided in C2000Ware. The FPUFastRTS is not as fast as the TMU but is definitely much faster than the RTS library function.

Refer to its user guide and associated examples for details. It also has benchmarks.

C:\ti\c2000\C2000Ware_4_03_00_00\libraries\math\FPUfastRTS\c28\docs

C:\ti\c2000\C2000Ware_4_03_00_00\libraries\math\FPUfastRTS\c28\examples

Thanks,

Sira

0 Damith Pavithra over 2 years ago in reply to Sira Rao80

Expert 1125 points

Thank you.

Whoever wrote examples in that library assumes we already know about fastRTS.very poor documentation.
For ex,in the attached file which i have found in the examples, i cannot find what is the meaning of Gold. and other variables also. Can you please explain this code to me.

Fullscreen fastrts_sine.c Download

//#############################################################################
//
//! \file   fastrts_sine.c
//!
//! \brief  Runs the sine routine
//! \author Vishal Coelho
//! \date   Sep 21, 2016
//
//  Group:          C2000
//  Target Device:  TMS320F28004x
//
//#############################################################################
//
//
// $Copyright: Copyright (C) 2023 Texas Instruments Incorporated -
//             http://www.ti.com/ ALL RIGHTS RESERVED $
//#############################################################################


//*****************************************************************************
// the includes
//*****************************************************************************
#include "fastrts_examples_setup.h"
#include "fastrts.h"
#include "fpu32/C28x_FPU_FastRTS.h"

//*****************************************************************************
// the defines
//*****************************************************************************
#define TEST_SIZE   (512U)
//*****************************************************************************
// the globals
//*****************************************************************************
// The global pass, fail values
uint16_t pass = 0U, fail = 0U;
// The absolute error between the result and expected values
float32_t tolerance = 2.5e-7;


float32_t test_output[TEST_SIZE];
float32_t test_error[TEST_SIZE];
//*****************************************************************************
// the function definitions
//*****************************************************************************
void FastRTS_runTest(void)
{
    // Locals
    uint16_t i;
    float32u_t in, out, gold, err;

    //<<VC160921: cant check ulp error as this only applies to
    // fixed point representation of the same set of numbers
    //
    //float32u_t errulp;
    //
    // VC160921>>

    for(i = 0U; i < TEST_SIZE; i++)
    {
        out.f32  = FLT_MAX;
        in.f32   = test_input[i];
        
        // Run the calculation function
        out.f32  = sinf(in.f32);

        test_output[i] = out.f32;
        gold.f32 = test_golden[i];
        err.f32  = fabsf(out.f32 - gold.f32);
        if(err.f32 < tolerance)
        {
            pass++;
        }
        else
        {
            fail++;
        }
        test_error[i] = err.f32;
    }
}

// End of File

0 Sira Rao80 over 2 years ago in reply to Damith Pavithra

TI__Mastermind 26000 points

Appreciate your feedback and noted.

However, I can answer a specific question if you have one.

The code takes an input, generates an output, and compares it a golden reference to determine Pass/Fail.

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28069: How use sine and cos math tables in boot rom