ADS1293: ADS1293 DRDYB Interrupt signals stop

Register settings:

Thank you for the answer.

I was initially relying on the 1M pullup resisor on the EVM board, and did temporarily enable the internal pullups of the teensy and even added some external pullups. I will give 10k resistors another try tomorrow though.

Additional pullup resistors do not help I've tested this again and I had tested this before (it was, at least in my opinion unlikely to be the problem - the ADS1293EVM does have an onboard pullup).  I've also flashed the MSP430 with other firmware to ensure it in not interfering somehow (just an idea) - I used the blink example code from the MSP430 Firmware Upgrade Example.

I've read through the data sheet again and can not find anything else that could cause this - as I understand it the only way to stop the conversion should be the writing the START_CON bit in the CONFIG register to 0. It is not 0 when the issue occurs.

Another thing I've checked again were the registers related to the interrupt (MASK_DRDYB and DRDYB_SRC):

DRDYB_SRC:  0 0   1 0 0 0

MASK_DRDYB: 0 0

(SYNCB_SRC: 0 0)

Which should be correct.

If someone has another idea as to why the ADS1293 would simply stop conversion/ stop sending out the interrupts, I'd be happy to hear it. I'm also adding the relevant bits of code here:

void ADS1293_3LeadECG() {
    uint8_t count, i = 0;
    uint8_t read_buf[CH_DATA_SIZE];
    uint32_t adc_data_ch1, adc_data_ch2;
    uint32_t count2 = 0;

    ADS1293_Reset();

    attachInterrupt(digitalPinToInterrupt(ADS1293_DataRdyPin), ADS1293_IntHandler, FALLING);
    attachInterrupt(digitalPinToInterrupt(ADS1293_AlarmPin), ADS1293_AlarmHandler, FALLING);

    ADS1293_WriteRegSettings3LeadECG();   // Set up ADS1293 for Channel Scan

    count = CH_DATA_SIZE;                                                        // bytes to read: ADC_DOUT2 - ADCDOUT0
    ADS1293_SPIWriteReg(ADS1293_CONFIG_REG, ADS1293_START);
    while (1) {
        if (ADS1293_DataRdy == 1) {
            ADS1293_SPIStreamReadReg(read_buf, count);                            // read adc output into read_buf

            // format raw adc output data
            adc_data_ch1 = ((uint32_t)read_buf[0] << 16) | ((uint16_t)read_buf[1] << 8) | read_buf[2];
            adc_data_ch2 = ((uint32_t)read_buf[3] << 16) | ((uint16_t)read_buf[4] << 8) | read_buf[5];

            Serial.printf("%d\t %d\t\n", adc_data_ch1, adc_data_ch2);

            if (++i == SAMPLE_ARRAY_SIZE)    i = 0;        // sample array is full

            ADS1293_DataRdy = 0;                                                // clear flag
        }
        if (ADS1293_Alarm == 1) {
            Serial.println("ADS1293: An error has occured:");


            Serial.printf("ERROR_LOD: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_LOD_REG)));
            Serial.printf("ERROR_STATUS: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_STATUS_REG)));
            Serial.printf("ERROR_RANGE1: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_RANGE1_REG)));
            Serial.printf("ERROR_RANGE2: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_RANGE2_REG)));
            Serial.printf("ERROR_RANGE3: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_RANGE3_REG)));
            Serial.printf("ERROR_SYNC: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_SYNC_REG)));
            Serial.printf("ERROR_MISC: %d\n", convertDecimalToBinary(ADS1293_SPIReadReg(ADS1293_ERROR_MISC_REG)));

            // clear ADS1293_Alarm flag
            ADS1293_Alarm = 0;
        }
    }
}

void ADS1293_SPIStreamReadReg(uint8_t* buffer, uint8_t count) {
  ADS1293_CsSet();
  SPI.transfer(ADS1293_READ_BIT + ADS1293_DATA_LOOP_REG); //Set address to initial register

  for (uint8_t i = 0; i < count; i++) {
    buffer[i] = SPI.transfer(0x00);
  }
  ADS1293_CsReset();
}

Interrupt is set on falling edge, ISR simply sets the interrupt flag to 1.

Registers configured as follows: