TMS320F280049C: 15c2214000401

Part Number: TMS320F280049C

Hello,

i in the development of the SDFM and I'm a bit stuck.

I generate PWM signal of 5 MHz for the filter module, and SOCA of PWM7 in 16 KHz for the interrupt.

I get data, but the scale is wrong. I am working on OSR of 64 and from my calculation the exchange value needed to be 6E-6. In practice the value is around 25E-5

The data readings look very linear. i.e. after translation, the value that I get from the SDFM are very close to my current supplier.

did i do something wrong or miss something?

i have attached my code below:

//###########################################################################
//
// FILE:   sdfm_ex4_pwm_sync_cpuread.c
//
// TITLE:  SDFM PWM Sync Example
//
//! \addtogroup driver_example_list
//! <h1> SDFM PWM Sync </h1>
//!
//! In this example, SDFM filter data is read by CPU in SDFM ISR routine. The
//! SDFM configuration is shown below:
//!     - SDFM1 is used in this example.
//!     - MODE0 Input control mode selected
//!     - Comparator settings
//!         - Sinc3 filter selected
//!         - OSR = 32
//!         - hlt = 0x7FFF (Higher threshold setting)
//!         - llt  = 0x0000(Lower threshold setting)
//!  -  Data filter settings
//!      - All the 4 filter modules enabled
//!      - Sinc3 filter selected
//!      - OSR = 256
//!      - All the 4 filters are synchronized by using PWM
//!       (Master Filter enable bit)
//!      - Filter output represented in 16 bit format
//!      - In order to convert 25 bit Data filter
//!        into 16 bit format user needs to right shift by 10 bits for
//!        Sinc3 filter with OSR = 256
//!  - Interrupt module settings for SDFM filter
//!      - All the 4 higher threshold comparator interrupts disabled
//!      - All the 4 lower threshold comparator interrupts disabled
//!      - All the 4 modulator failure interrupts disabled
//!      - All the 4 filter will generate interrupt when a new filter data
//!        is available
//!
//! \b External \b Connections \n
//!    Connect Sigma-Delta streams to (SD-D1, SD-C1 to SD-D4,SD-C4)
//!    on GPIO24-GPIO31
//!
//! \b Watch \b Variables \n
//! -  \b filter1Result - Output of filter 1
//! -  \b filter2Result - Output of filter 2
//! -  \b filter3Result - Output of filter 3
//! -  \b filter4Result - Output of filter 4
//!
//
//###########################################################################
//
//
// $Copyright:
// Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions 
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// 
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//   notice, this list of conditions and the following disclaimer.
// 
//   Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the 
//   documentation and/or other materials provided with the   
//   distribution.
// 
//   Neither the name of Texas Instruments Incorporated nor the names of
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// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################

//
// Included Files
//
#include "driverlib.h"
#include "device.h"
#include <stdio.h>

//
// Defines
//
#define MAX_SAMPLES               256
#define EPWM_TIMER_TBPRD          10  // ePWM Period register

//
// Globals
//

uint32_t sdfmInstance;
uint32_t pwmInstance = EPWM8_BASE; // ePWM 8 for synchronizing SDFM1 filters
//int16_t  filter1Result[MAX_SAMPLES];
int16_t  filter2Result[MAX_SAMPLES];
int16_t  filter3Result[MAX_SAMPLES];
//int16_t  filter4Result[MAX_SAMPLES];
float32_t  TrueResult[MAX_SAMPLES];
float32_t  AvgData = 0;
float32_t  TrancFactor = 0.000242;

#pragma DATA_SECTION(filter2Result, "Filter2_RegsFile");
#pragma DATA_SECTION(filter3Result, "Filter3_RegsFile");


//
// Function Prototypes
//

void configureSDFM_CLK_Pins(void);
void configureSDFMPins(void);
void initEPWM(uint32_t epwmInstance);
__interrupt void sdfm1ErrorISR(void);
__interrupt void sdfmDR1ISR(void);
void AnalizeData();
void CalcAvg();


//
// Main
//
void main(void)
{
   uint16_t  hlt, llt;

   //
   // Initialize device clock and peripherals
   //
   Device_init();

   //
   // Setup GPIO by disabling pin locks and enabling pullups
   //
   Device_initGPIO();

   //
   // Initialize PIE and clear PIE registers. Disables CPU interrupts.
   //
   Interrupt_initModule();

   //
   // Initialize the PIE vector table with pointers to the shell Interrupt
   // Service Routines (ISR).
   //
   Interrupt_initVectorTable();

   //
   // Interrupts that are used in this example are re-mapped to
   // ISR functions found within this file.
   //
   Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP3);
   Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP5);
   Interrupt_register(INT_SDFM1DR2, sdfmDR1ISR);
   Interrupt_register(INT_SDFM1, sdfm1ErrorISR);

   //
   // Enable SDFM1 Error and DR interrupts
   //
   Interrupt_enable(INT_SDFM1);
   Interrupt_enable(INT_SDFM1DR2);
   Interrupt_enable(INT_SDFM1DR3);
   Interrupt_enable(INT_EPWM8);

   //
   // Configure GPIO pins as SDFM pins
   //
   configureSDFMPins();
   configureSDFM_CLK_Pins();

    //
    // Select SDFM1
    //
    sdfmInstance = SDFM1_BASE;

    //
    // Input Control Module:
    // Configure Modulator Clock rate = Modulator data rate
    //

    SDFM_setupModulatorClock(sdfmInstance, SDFM_FILTER_2,
                             SDFM_MODULATOR_CLK_HALF_DATA_RATE);

    SDFM_setupModulatorClock(sdfmInstance, SDFM_FILTER_3,
                             SDFM_MODULATOR_CLK_EQUAL_DATA_RATE);

    //
    // Comparator Module
    //
    hlt = 0x7FFF;    //Over value threshold settings
    llt = 0x0000;    //Under value threshold settings

    //
    // Data filter Module
    //
    // Configure Data filter modules filter type, OSR value and
    // enable / disable data filter
    //

    SDFM_configDataFilter(sdfmInstance, (SDFM_FILTER_2 | SDFM_FILTER_SINC_3 |
           SDFM_SET_OSR(64)), (SDFM_DATA_FORMAT_16_BIT | SDFM_FILTER_ENABLE |
           SDFM_SHIFT_VALUE(0x0004)));

    SDFM_configDataFilter(sdfmInstance, (SDFM_FILTER_3 | SDFM_FILTER_SINC_3 |
           SDFM_SET_OSR(64)), (SDFM_DATA_FORMAT_16_BIT | SDFM_FILTER_ENABLE |
           SDFM_SHIFT_VALUE(0x0004)));

    //
    // Enable Master filter bit: Unless this bit is set none of the filter modules
    // can be enabled. All the filter modules are synchronized when master filter
    // bit is enabled after individual filter modules are enabled.
    //
    SDFM_enableMasterFilter(sdfmInstance);

    //
    // PWM signals can synchronize SDFM1 filters. Enabling PWM sync for SDFM
    // filters.
    //
    SDFM_enableExternalReset(sdfmInstance, SDFM_FILTER_2);
    SDFM_enableExternalReset(sdfmInstance, SDFM_FILTER_3);

    SDFM_setPWMSyncSource(sdfmInstance, SDFM_FILTER_2, SDFM_SYNC_PWM7_SOCA);
    SDFM_setPWMSyncSource(sdfmInstance, SDFM_FILTER_3, SDFM_SYNC_PWM8_SOCA);

    //
    // Init EPWMs
    //
    initEPWM(pwmInstance);

    //
    // Enable interrupts
    //
    // Following SDFM interrupts can be enabled / disabled using this function.
    //  Enable / disable comparator high threshold
    //  Enable / disable comparator low threshold
    //  Enable / disable modulator clock failure
    //  Enable / disable filter acknowledge
    //
    SDFM_enableInterrupt(sdfmInstance, SDFM_FILTER_2,
         (    SDFM_DATA_FILTER_ACKNOWLEDGE_INTERRUPT));

    SDFM_enableInterrupt(sdfmInstance, SDFM_FILTER_3,
            ( SDFM_DATA_FILTER_ACKNOWLEDGE_INTERRUPT));

    SDFM_disableInterrupt(sdfmInstance, SDFM_FILTER_2,
            (SDFM_HIGH_LEVEL_THRESHOLD_INTERRUPT |
             SDFM_LOW_LEVEL_THRESHOLD_INTERRUPT));

    SDFM_disableInterrupt(sdfmInstance, SDFM_FILTER_3,
            (SDFM_HIGH_LEVEL_THRESHOLD_INTERRUPT |
             SDFM_LOW_LEVEL_THRESHOLD_INTERRUPT));

    while((HWREGH(pwmInstance + EPWM_O_TBCTR)) < EPWM_TIMER_TBPRD);

    //
    // Enable master interrupt so that any of the filter interrupts can trigger
    // by SDFM interrupt to CPU
    //
    SDFM_enableMasterInterrupt(sdfmInstance);

    //
    // Enable Global Interrupt (INTM) and realtime interrupt (DBGM)
    //
    EINT;
    ERTM;

    while(1)
    {
        AnalizeData();
        CalcAvg();
    };
}

//
// sdfm1ErrorISR - SDFM1 Error ISR
//
__interrupt void sdfm1ErrorISR(void)
{
    //
    // Clear SDFM flag register (SDIFLG)
    //
    SDFM_clearInterruptFlag(SDFM1_BASE, SDFM_MASTER_INTERRUPT_FLAG |
                            0xFFFF);

    //
    // Acknowledge this interrupt to receive more interrupts from group 5
    //
    Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP5);
}

//
// sdfmDR1ISR - SDFM DR1 ISR
//
__interrupt void sdfmDR1ISR(void)
{
    static uint16_t loopCounter1 = 0;

    SDFM_setOutputDataFormat(SDFM1_BASE, SDFM_FILTER_2,
                             SDFM_DATA_FORMAT_16_BIT);

    //
    // Read SDFM flag register (SDIFLG)
    //
    if(loopCounter1 >= MAX_SAMPLES)
    {
        loopCounter1 = 0;
    }

    filter2Result[loopCounter1] =
           (int16_t)(SDFM_getFilterData(SDFM1_BASE, SDFM_FILTER_2) >> 16U);
    filter3Result[loopCounter1++] =
           (int16_t)(SDFM_getFilterData(SDFM1_BASE, SDFM_FILTER_3) >> 16U);

    //
    // Clear SDFM flag register (SDIFLG)
    //
    SDFM_clearInterruptFlag(SDFM1_BASE, SDFM_MASTER_INTERRUPT_FLAG |
                            SDFM_FILTER_2_NEW_DATA_FLAG            |
                            SDFM_FILTER_3_NEW_DATA_FLAG );


    //
    // Acknowledge this interrupt to receive more interrupts from group 5
    //
    Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP5);
}




void AnalizeData()
{
    int i = 0;

    for (i = 0; i < MAX_SAMPLES; ++i)
    {
        TrueResult[i] = ((float32_t)filter2Result[i] * TrancFactor);
    }
}

void CalcAvg()
{
    int i = 0;
    float32_t tmpAvg = 0.0;
    for (i = 0; i < MAX_SAMPLES; ++i)
    {
        tmpAvg += TrueResult[i];
    }

    AvgData = tmpAvg / MAX_SAMPLES;
}



//
// configureSDFMPins - Configure SDFM GPIOs
//
void configureSDFMPins(void)
{
    uint16_t pin;
    for(pin = 24; pin <= 31; pin++)
    {
        GPIO_setDirectionMode(pin, GPIO_DIR_MODE_IN);
        GPIO_setMasterCore(pin, GPIO_CORE_CPU1);
        GPIO_setPadConfig(pin, GPIO_PIN_TYPE_STD);
        GPIO_setQualificationMode(pin, GPIO_QUAL_ASYNC);
    }

    //
    // Configure GPIO16-GPIO31 as SDFM pins
    //

    GPIO_setPinConfig(GPIO_26_SD1_D2);
    GPIO_setPinConfig(GPIO_27_SD1_C2);
    GPIO_setPinConfig(GPIO_28_SD1_D3);
    GPIO_setPinConfig(GPIO_29_SD1_C3);
}

void configureSDFM_CLK_Pins(void)
{
    uint16_t pin = 14;
    GPIO_setDirectionMode(pin, GPIO_DIR_MODE_OUT);
    GPIO_setMasterCore(pin, GPIO_CORE_CPU1);
    GPIO_setPadConfig(pin, GPIO_PIN_TYPE_STD);
    GPIO_setQualificationMode(pin, GPIO_QUAL_SYNC);
    GPIO_setPinConfig(GPIO_14_EPWM8_A);
}

//
// done - Function to halt debugger and stop application
//
void done(void)
{
    asm(" ESTOP0");
    for(;;);
}

//
// initEPWM - Initialize specified EPWM settings
//

void initEPWM(uint32_t epwmInstance)
{
    //
    // Disable sync(Freeze clock to PWM as well)
    //
    SysCtl_disablePeripheral(SYSCTL_PERIPH_CLK_TBCLKSYNC);

    //
    // Setup TBCLK: Configure timer period = 801 TBCLKs, phase = 0 &
    // clear counter
    //
    EPWM_setTimeBasePeriod(epwmInstance, EPWM_TIMER_TBPRD);
    EPWM_setTimeBasePeriod(EPWM7_BASE, 3125);
    EPWM_setPhaseShift(epwmInstance, 0U);
    EPWM_setPhaseShift(EPWM7_BASE, 0U);
    EPWM_setTimeBaseCounter(epwmInstance, 0U);
    EPWM_setTimeBaseCounter(EPWM7_BASE, 0U);

    //
    // Set CMPA value
    //
    EPWM_setCounterCompareValue(epwmInstance, EPWM_COUNTER_COMPARE_A, 4U);
    EPWM_setCounterCompareValue(epwmInstance, EPWM_COUNTER_COMPARE_B, 0U);
//    EPWM_setCounterCompareValue(EPWM7_BASE, EPWM_COUNTER_COMPARE_A, 480U);
    EPWM_setCounterCompareValue(EPWM7_BASE, EPWM_COUNTER_COMPARE_B, 2645U);

    //
    // Setup counter mode
    //
    EPWM_setTimeBaseCounterMode(epwmInstance, EPWM_COUNTER_MODE_UP);
    EPWM_setClockPrescaler(epwmInstance, EPWM_CLOCK_DIVIDER_1, EPWM_HSCLOCK_DIVIDER_1);
    EPWM_setTimeBaseCounterMode(EPWM7_BASE, EPWM_COUNTER_MODE_UP);
    EPWM_setClockPrescaler(EPWM7_BASE, EPWM_CLOCK_DIVIDER_1, EPWM_HSCLOCK_DIVIDER_1);
    //
    // Set actions:
    // Toggle PWMxA on event A, up-count
    // Toggle PWMxB on event A, up-count
    //
    EPWM_setActionQualifierAction(EPWM8_BASE,
                                  EPWM_AQ_OUTPUT_A,
                                  EPWM_AQ_OUTPUT_TOGGLE,
                                  EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(EPWM8_BASE,
                                  EPWM_AQ_OUTPUT_B,
                                  EPWM_AQ_OUTPUT_TOGGLE,
                                  EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(EPWM7_BASE,
                                  EPWM_AQ_OUTPUT_A,
                                  EPWM_AQ_OUTPUT_TOGGLE,
                                  EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(EPWM7_BASE,
                                  EPWM_AQ_OUTPUT_B,
                                  EPWM_AQ_OUTPUT_NO_CHANGE,
                                  EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    //
    // Configure SOCA signal
    //
    //
    EPWM_setADCTriggerSource(EPWM7_BASE, EPWM_SOC_A, EPWM_SOC_TBCTR_U_CMPA);
    EPWM_setADCTriggerEventPrescale(EPWM7_BASE, EPWM_SOC_A, 1);

    //
    // Enable sync and clock to PWM
    //
    SysCtl_enablePeripheral(SYSCTL_PERIPH_CLK_TBCLKSYNC);
}

//
// End of file
//

Thanks

Ofri