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CCS/EVM430-FR6047: EVM430-FR6047

user5137323
Prodigy 170 points

Part Number: EVM430-FR6047
Other Parts Discussed in Thread: MSP430FR6047

Tool/software: Code Composer Studio

hello,I have the EVM430-FR6047, and I have done the PCB using MSP430FR6047 by myself, my code  reference the demo code of the EVM430-FR6047.

My measuring result as follows:

The  σ = 527  , this is too large.

I think, the capture waveform is not symmetry, the positive amplitude is greater than the negative amplitude.

Am I right？

And，I modification my code , as follows:

HWREG16(SAPH_BASE + OFS_SAPHBCTL) &= ~(PGABIAS_3);
HWREG16(SAPH_BASE + OFS_SAPHBCTL) |= (PGABIAS_3);

But , the register SAPHBCTL is not change. 

Why is this?

Thanks.

  • 0
    TI__Mastermind 47265 points
    Hello,

    The signal is a bit high, so you could be clipping the signal. Start by reducing the gain. You can do this from the parameters tab of the GUI. Try to get the signal down to about 800 codes. Let me know if this gets you in a better standard deviation range.

    In regards to the register not changing, let me look into this further and I will get back with you.
  • 0 in reply to Eddie LaCost
    Prodigy 170 points
    Hello，thank you very much.
    I have reduced the gain, and get a bit better in standard deviation range.
    I have a new question:
    USS_SW_LIB_APP_FILTER_COEFFICIENTS in USS_userConfig.h as follows

    #define USS_SW_LIB_APP_FILTER_COEFFICIENTS \
    { \
    /* USS_filterCoeffs_3400000Hz */ \
    { 0x0000, 0xFEEA, 0xFFDA, 0xF4E6, \
    0xFBA5, 0xFFBB, 0x03BC, 0x155D, \
    0xDE0E, 0xF5A0, 0x2E9C, 0xF5A0, \
    0xDE0E, 0x155D, 0x03BC, 0xFFBB, \
    0xFBA5, 0xF4E6, 0xFFDA, 0xFEEA \
    }, \
    /* USS_filterCoeffs_3600000Hz */ \
    { 0x0000, 0x002B, 0xFF01, 0xF563, \
    0x050D, 0xFE4C, 0x0F1B, 0x0FDC, \
    0xE05C, 0xFAC9, 0x302A, 0xFAC9, \
    0xE05C, 0x0FDC, 0x0F1B, 0xFE4C, \
    0x050D, 0xF563, 0xFF01, 0x002B \
    }, \
    /* USS_filterCoeffs_3800000Hz */ \
    { 0x0000, 0x0120, 0xFAD8, 0xFA10, \
    0x06E7, 0xFE1E, 0x14A0, 0x0848, \
    0xE00B, 0xFE43, 0x2DAF, 0xFE43, \
    0xE00B, 0x0848, 0x14A0, 0xFE1E, \
    0x06E7, 0xFA10, 0xFAD8, 0x0120 \
    }, \
    /* USS_filterCoeffs_4000000Hz */ \
    { 0x0000, 0x0000, 0xF68E, 0x0000, \
    0x037C, 0x0000, 0x1714, 0x0000, \
    0xE229, 0x0000, 0x2D64, 0x0000, \
    0xE229, 0x0000, 0x1714, 0x0000, \
    0x037C, 0x0000, 0xF68E, 0x0000 \
    }, \
    /* USS_filterCoeffs_Custom */ \
    {0}, \
    };

    And I need to modify the FILTER_COEFFICIENTS , my transducer excitation frequency is 1.4MHz, sampling frequency is 8M, ADC over sampling rate is 10. I use the following matlab code , as same as the Application Report SLAA837 :

    N = 18;
    Fs = 8000000; %采样频率
    Fstop1 = 1000000; %Stopband Frequency
    Fpass1 = 1200000; %Passband Frequency
    Fpass2 = 1600000;
    Fstop2 = 1800000;
    Wstop1 = 1; % Stopband Attenuation
    Wpass = 10; % Passband Ripple
    Wstop2 = 1; % Stopband Attenuation
    my_filterCoeffs = [firpm(N,[0 Fstop1 Fpass1 Fpass2 Fstop2 Fs/2]/(Fs/2), [0 0 1 1 0 0],[Wstop1 Wpass Wstop2]) 0]

    My result is :
    my_filterCoeffs=[0.0410 0.0923 -0.0705 0.2461
    0.1170 -0.0491 -0.1576 -0.0906
    0.0701 0.1542 0.0701 -0.0906
    -0.1576 -0.0491 0.1170 0.2461
    -0.0705 0.0923 0.0410 0]

    How can i convert my float result to the fix point USS_SW_LIB_APP_FILTER_COEFFICIENTS ?

    Thanks.

    In regards to the register not changing,do you have answer?

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