Diff: main.cpp

Revision:

1:471e2b722d24

Parent:

0:0bd4103885bf

Child:

2:54182d6a168f

diff -r 0bd4103885bf -r 471e2b722d24 main.cpp
--- a/main.cpp	Thu Aug 17 15:53:16 2017 +0000
+++ b/main.cpp	Mon Aug 21 15:43:51 2017 +0000
@@ -7,65 +7,56 @@
 bool op_sensor_config(MAX30101 &op_sensor);
 
 /* Op Sensor FIFO nearly full callback */
-volatile bool op_sensorIntFlag = false;                  
+volatile bool op_sensorIntFlag = 0;                  
 void op_sensor_callback()
 {
-    op_sensorIntFlag = true;
+    op_sensorIntFlag = 1;
 }
 
 int main()
 {
-    Serial pc(USBTX, USBRX);
-    pc.baud(115200);
+    Serial pc(USBTX, USBRX);            // Use USB debug probe for serial link
+    pc.baud(115200);                    // Baud rate = 115200
     
-    DigitalOut rLed(LED1, LED_OFF);
+    DigitalOut rLed(LED1, LED_OFF);     // Debug LEDs
     DigitalOut gLed(LED2, LED_OFF);
     DigitalOut bLed(LED3, LED_OFF);
     
-    InterruptIn op_sensor_int(P3_2);
+    InterruptIn op_sensor_int(P3_2);            // Config P3_2 as int. in for
+    op_sensor_int.fall(&op_sensor_callback);    // FIFO ready interrupt
     
-    I2C i2cBus(I2C1_SDA, I2C1_SCL);                 // I2C bus
+    I2C i2cBus(I2C1_SDA, I2C1_SCL);     // I2C bus, P3_4 = SDA, P3_5 = SCL 
 
     MAX30101 * op_sensor;
     op_sensor = new MAX30101(i2cBus);
-    int rc = op_sensor_config(*op_sensor); 
-    
-    op_sensor_int.fall(op_sensor_callback);
+    int rc = op_sensor_config(*op_sensor);
     
     MAX30101::InterruptBitField_u ints;
     uint8_t fifoData[MAX30101::MAX_FIFO_BYTES];
     uint16_t idx, readBytes;
     while(1) {
         
-        if( rc == 0 ) 
-        {
+        if( rc == 0 ) {
             
-            if(op_sensorIntFlag) 
-            {
-                
+            if(op_sensorIntFlag) {
                 pc.printf("Interrupt seen...\r\n");
-                op_sensorIntFlag = false; 
-                rc = op_sensor->getInterruptStatus(ints);
+                op_sensorIntFlag = 0;                       // Lower interrupt flag
+                rc = op_sensor->getInterruptStatus(ints);   // Read interrupt status 
                 
-                if((rc == 0) && (ints.bits.a_full)) 
-                {
+                if((rc == 0) && (ints.bits.a_full)) {
+                    rc = op_sensor->readFIFO(MAX30101::OneLedChannel, fifoData, readBytes);     // Read FIFO 
                     
-                    rc = op_sensor->readFIFO(MAX30101::OneLedChannel, fifoData, readBytes);
-                    
-                    if(rc == 0) 
-                    {
-                        
+                    if(rc == 0) {
                         pc.printf("FIFO Read, received %d bytes\r\n", readBytes);
                         
-                        for(idx = 0; idx < readBytes; idx++) 
-                        {
-                            pc.printf("fifoData[0x%04x] = 0x%02x\r\n", idx, fifoData[idx]); 
+                        for(idx = 0; idx < readBytes; idx++) {
+                            pc.printf("fifoData[0x%04x] = 0x%02x\r\n", idx, fifoData[idx]);     // Print results
                         }
                         pc.printf("\r\n");
                     }
                 }
             }
-                
+                    
         } else {
             
             pc.printf("Something went wrong, check the I2C bus or power connections... \r\n");
@@ -99,8 +90,8 @@
     if(rc == 0)
     {
         ints.all = 0;
-        ints.bits.die_temp = 1;
-        ints.bits.a_full = 1;
+        ints.bits.die_temp = 1;     // Enable FIFO almost full interrupt
+        ints.bits.a_full = 1;       // Enable internal die temp. interrupt
         rc = op_sensor.enableInterrupts(ints);
     }
     
@@ -109,16 +100,16 @@
     if(rc == 0)
     {
         fifoConfig.all = 0;
-        fifoConfig.bits.fifo_a_full = 15; //Max level of 15 samples
-        fifoConfig.bits.sample_average = MAX30101::AveragedSamples_4; 
+        fifoConfig.bits.fifo_a_full = 15; // Max level of 15 samples 
+        fifoConfig.bits.sample_average = MAX30101::AveragedSamples_4; // Average 4 samples
         rc = op_sensor.setFIFOConfiguration(fifoConfig);
     }
     
     MAX30101::SpO2Configuration_u spo2Config;
-    spo2Config.all = 0;
-    spo2Config.bits.spo2_sr = MAX30101::SR_1600_Hz;
     if(rc == 0)
     {
+        spo2Config.all = 0;
+        spo2Config.bits.spo2_sr = MAX30101::SR_400_Hz;      // SpO2 SR = 400Hz
         rc = op_sensor.setSpO2Configuration(spo2Config);
     }
     
@@ -126,14 +117,14 @@
     if(rc == 0)
     {
         //Heart Rate only
-        rc = op_sensor.setLEDPulseAmplitude(MAX30101::LED1_PA, 0x1F);
+        rc = op_sensor.setLEDPulseAmplitude(MAX30101::LED1_PA, 0x1F); // LED1 = 6.4mA
     }
        
     //Set operating mode
     modeConfig.all = 0;
-    modeConfig.bits.mode = MAX30101::HeartRateMode;
     if(rc == 0)
     {
+        modeConfig.bits.mode = MAX30101::HeartRateMode;     // Heart-rate only
         rc = op_sensor.setModeConfiguration(modeConfig);
     }