File content as of revision 3:420d5efbd967:

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

MAX32630FTHR pegasus(MAX32630FTHR::VIO_3V3);

void ecg_config(MAX30003 &ecgAFE);

/* ECG FIFO nearly full callback */
volatile bool ecgFIFOIntFlag = 0; 
void ecgFIFO_callback()  {
    
    ecgFIFOIntFlag = 1;

}  

int main()
{   
    const int RTOR_STATUS_MASK = ( 1<<10 );
    const int EINT_STATUS_MASK = ( 1<<23 );
    
    Serial pc(USBTX, USBRX);            // Use USB debug probe for serial link
    pc.baud(115200);                    // Baud rate = 115200
    
    DigitalOut rLed(LED1, LED_OFF);      // Debug LEDs
    DigitalOut gLed(LED2, LED_OFF);
    DigitalOut bLed(LED3, LED_OFF);
    
    InterruptIn ecgFIFO_int(P5_4);          // Config P5_4 as int. in for the
    ecgFIFO_int.fall(&ecgFIFO_callback);    // ecg FIFO almost full interrupt
    
    SPI spiBus(SPI2_MOSI, SPI2_MISO, SPI2_SCK);     // SPI bus, P5_1 = MOSI, 
                                                    // P5_2 = MISO, P5_0 = SCK
    
    MAX30003 * ecgAFE;
    ecgAFE = new MAX30003(spiBus, P5_3);    // New MAX30003 on spiBus, CS = P5_3 
    ecg_config(*ecgAFE);                    // Config ECG 
     
    
    ecgAFE->writeRegister( MAX30003::SYNCH , 0);
    
    uint32_t ecgFIFO, readSamples, idx, ETAG[32], status, RtoR;
    int16_t ecgSample[32];
    float BPM;
    
    while(1) {
        
        /* Read back ECG samples from the FIFO */
        if( ecgFIFOIntFlag ) {
            pc.printf("Interrupt received....\r\n");
            status = ecgAFE->readRegister( MAX30003::STATUS );      // Read the STATUS register
            pc.printf("Status : 0x%x\r\n"
                      "Current BPM is %3.2f\r\n\r\n", status, BPM);
            
            // Check if R-to-R interrupt asserted
            if( ( status & RTOR_STATUS_MASK ) == RTOR_STATUS_MASK ){              // Check if RtoR update
            
                ecgFIFOIntFlag = 0;
                pc.printf("R-to-R Interrupt \r\n");
                RtoR = ecgAFE->readRegister( MAX30003::RTOR );  // Read RtoR register
                BPM = 60.0*RtoR/32768.0;                        // Convert to BPM
                pc.printf("RtoR : %d\r\n\r\n", RtoR);           // Print BPM/RtoR
                
            } 
             
            // Check if EINT interrupt asserted
            if ( ( status & EINT_STATUS_MASK ) == EINT_STATUS_MASK ) {     
            
                ecgFIFOIntFlag = 0; 
                pc.printf("FIFO Interrupt \r\n");
                readSamples = 0;                        // Reset sample counter
                
                do {
                    ecgFIFO = ecgAFE->readRegister( MAX30003::ECG_FIFO );   // Read FIFO
                    ecgSample[readSamples] = ecgFIFO >> 8;                  // Isolate voltage data
                    ETAG[readSamples] = ( ecgFIFO >> 3 ) & 0b111;           // Isolate ETAG
                    readSamples++;                                          // Increment sample counter
                
                // Check that sample is not last sample in FIFO                                              
                } while ( ETAG[readSamples-1] == 0x0 || 
                          ETAG[readSamples-1] == 0x1 ); 
            
                pc.printf("%d samples read from FIFO \r\n", readSamples);
                
                // Check if FIFO has overflowed
                if( ETAG[readECGSamples - 1] == 0x7 ){                  
                    ecgAFE.writeRegister( MAX30003::FIFO_RST , 0); // Reset FIFO
                }
                
                /* Print results */
                for( idx = 0; idx < readSamples; idx++ ) {
                    pc.printf("Sample : %6d, \tETAG : 0x%x\r\n", ecgSample[idx], ETAG[idx]);           
                }
                pc.printf("\r\n\r\n\r\n");                          
            }
        
        }
    }
}




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.bits.en_eint = 1;              // Enable EINT interrupt
    EN_INT_r.bits.en_rrint = 1;             // Enable 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);
       
    
    return;
}