File content as of revision 8:6b9359f81cc0:

#include "MAX30003.h"
#include "mbed.h"
#include "max32630fthr.h"


MAX32630FTHR pegasus(MAX32630FTHR::VIO_3V3);

void ecg_config(MAX30003 &ecgAFE);

volatile bool ecgFIFOIntFlag = 0; 
void ecgFIFO_callback_1()  { // Triggered when the ECG FIFO is about to be full
    
    ecgFIFOIntFlag = 1;

}  

int main()
{   

    // Constants
    const int EINT_STATUS_MASK =  1 << 23;
    const int FIFO_OVF_MASK =  0x7;
    const int FIFO_VALID_SAMPLE_MASK =  0x0;
    const int FIFO_FAST_SAMPLE_MASK =  0x1;
    const int ETAG_BITS_MASK = 0x7;
    DigitalOut rLed(LED1, LED_OFF);
    
    Serial pc(USBTX, USBRX);            // Use USB debug probe for serial link
    pc.baud(115200);                    // Baud rate = 115200
    
    InterruptIn ecgFIFO_int(P5_4);          // Config P5_4 as int. in for the
    ecgFIFO_int.fall(&ecgFIFO_callback_1);    // ecg FIFO interrupt at falling edge
    
    SPI spiBus(SPI2_MOSI, SPI2_MISO, SPI2_SCK);     // SPI bus, P5_1 = MOSI, 
                                                    // P5_2 = MISO, P5_0 = SCK
    
    MAX30003 ecgAFE(spiBus, P5_3);          // New MAX30003 on spiBus, CS = P5_3 
    
    ecg_config(ecgAFE);                    // Config ECG 
     
    
    ecgAFE.writeRegister( MAX30003::SYNCH , 0);
    
    uint32_t ecgFIFO, readECGSamples, idx, ETAG[32], status;
    int16_t ecgSample[32];
    
    while(1) {
        
        // Read back ECG samples from the FIFO 
        if( ecgFIFOIntFlag ) {
            
            ecgFIFOIntFlag = 0; 
            status = ecgAFE.readRegister( MAX30003::STATUS );      // Read the STATUS register
             
            // Check if EINT interrupt asserted
            if ( ( status & EINT_STATUS_MASK ) == EINT_STATUS_MASK ) {     
            
                readECGSamples = 0;                        // Reset sample counter
                
                do {
                    ecgFIFO = ecgAFE.readRegister( MAX30003::ECG_FIFO );       // Read FIFO
                    ecgSample[readECGSamples] = ecgFIFO >> 8;                  // Isolate voltage data
                    ETAG[readECGSamples] = ( ecgFIFO >> 3 ) & ETAG_BITS_MASK;  // Isolate ETAG
                    readECGSamples++;                                          // Increment sample counter
                
                // Check that sample is not last sample in FIFO                                              
                } while ( ETAG[readECGSamples-1] == FIFO_VALID_SAMPLE_MASK || 
                          ETAG[readECGSamples-1] == FIFO_FAST_SAMPLE_MASK ); 
                
                // Check if FIFO has overflowed
                if( ETAG[readECGSamples - 1] == FIFO_OVF_MASK ){                  
                    ecgAFE.writeRegister( MAX30003::FIFO_RST , 0); // Reset FIFO
                    rLed = 1;//notifies the user that an over flow occured
                }
                
                // Print results 
                for( idx = 0; idx < readECGSamples; idx++ ) {
                    pc.printf("%6d\r\n", ecgSample[idx]);           
                } 
                               
            }
        }
    }
}




void ecg_config(MAX30003& ecgAFE) { 

    // Reset ECG to clear registers
    ecgAFE.writeRegister( MAX30003::SW_RST , 0);
    
    // General config register setting
    MAX30003::GeneralConfiguration_u CNFG_GEN_r;
    CNFG_GEN_r.bits.en_ecg = 1;     // Enable ECG channel
    CNFG_GEN_r.bits.rbiasn = 1;     // Enable resistive bias on negative input
    CNFG_GEN_r.bits.rbiasp = 1;     // Enable resistive bias on positive input
    CNFG_GEN_r.bits.en_rbias = 1;   // Enable resistive bias
    CNFG_GEN_r.bits.imag = 2;       // Current magnitude = 10nA
    CNFG_GEN_r.bits.en_dcloff = 1;  // Enable DC lead-off detection   
    ecgAFE.writeRegister( MAX30003::CNFG_GEN , CNFG_GEN_r.all);
        
    
    // ECG Config register setting
    MAX30003::ECGConfiguration_u CNFG_ECG_r;
    CNFG_ECG_r.bits.dlpf = 1;       // Digital LPF cutoff = 40Hz
    CNFG_ECG_r.bits.dhpf = 1;       // Digital HPF cutoff = 0.5Hz
    CNFG_ECG_r.bits.gain = 3;       // ECG gain = 160V/V
    CNFG_ECG_r.bits.rate = 2;       // Sample rate = 128 sps
    ecgAFE.writeRegister( MAX30003::CNFG_ECG , CNFG_ECG_r.all);
      
    
    //R-to-R configuration
    MAX30003::RtoR1Configuration_u CNFG_RTOR_r;
    CNFG_RTOR_r.bits.en_rtor = 1;           // Enable R-to-R detection
    ecgAFE.writeRegister( MAX30003::CNFG_RTOR1 , CNFG_RTOR_r.all);
       
        
    //Manage interrupts register setting
    MAX30003::ManageInterrupts_u MNG_INT_r;
    MNG_INT_r.bits.efit = 0b00011;          // Assert EINT w/ 4 unread samples
    MNG_INT_r.bits.clr_rrint = 0b01;        // Clear R-to-R on RTOR reg. read back
    ecgAFE.writeRegister( MAX30003::MNGR_INT , MNG_INT_r.all);
    
    
    //Enable interrupts register setting
    MAX30003::EnableInterrupts_u EN_INT_r;
    EN_INT_r.all = 0;
    EN_INT_r.bits.en_eint = 1;              // Enable EINT interrupt
    EN_INT_r.bits.en_rrint = 0;             // Disable R-to-R interrupt
    EN_INT_r.bits.intb_type = 3;            // Open-drain NMOS with internal pullup
    ecgAFE.writeRegister( MAX30003::EN_INT , EN_INT_r.all);
       
       
    //Dyanmic modes config
    MAX30003::ManageDynamicModes_u MNG_DYN_r;
    MNG_DYN_r.bits.fast = 0;                // Fast recovery mode disabled
    ecgAFE.writeRegister( MAX30003::MNGR_DYN , MNG_DYN_r.all);
    
    // MUX Config
    MAX30003::MuxConfiguration_u CNFG_MUX_r;
    CNFG_MUX_r.bits.openn = 0;          // Connect ECGN to AFE channel
    CNFG_MUX_r.bits.openp = 0;          // Connect ECGP to AFE channel
    ecgAFE.writeRegister( MAX30003::CNFG_EMUX , CNFG_MUX_r.all);
       
    return;
}