Diff: main.cpp

Revision:

2:c8b7ef52c65c

Parent:

1:f62247cbeac6

Child:

3:a7df33374b48

--- a/main.cpp	Wed Jan 04 17:00:53 2017 +0000
+++ b/main.cpp	Wed Jan 04 23:14:42 2017 +0000
@@ -75,9 +75,12 @@
 #define PartIDReg 0xFF
 #define maxi2cFreq 1000000
 #define recommendedi2cFreq 400000
+#define interrupt_pin D12 //INTB pin --see InterruptIn declaration
 #define maxECGrate 0
 #define normECGrate 1
-const int16_t i2cBufferSize=32;
+#define BaudRate 921600 
+//also try 921600, 460800 230400
+const int16_t i2cBufferSize=36; //32 was stable. In this rev exploring 36
 
 //global variables
 
@@ -85,6 +88,7 @@
 const uint8_t ppgOn = 1; //turn on PPG (IR and Red both)
 const uint8_t ecgOn = 1; //turn on ECG measurement
 const uint8_t etiOn = 1; //turn on ETI (lead check) electrical tissue impedance. Checks if your fingers are on or not.
+//const uint8_t ecgRate = maxECGrate; //use normECGrate 800Hz or maxECGrate 1600Hz
 const uint8_t ecgRate = maxECGrate; //use normECGrate 800Hz or maxECGrate 1600Hz
 const int16_t printEvery = 5 *(2-ecgRate); //print data only every X samples to reduce serial data BW (print fewer for faster sampling)
 const int16_t ppgBits2Avg = 0; //log(2) of IIR filter divisor, data = data + (new_data-data)>>bits2Avg for PPG IR and R, use 0 for no averaging
@@ -108,7 +112,7 @@
 
 //NOT USER CONFIGURABLE******************
 
-#define interrupt_pin D12 //INTB pin --see InterruptIn declaration
+
 const int16_t irChannel = ppgOn-1; //-1 or 0
 const int16_t rChannel = ppgOn*(2)-1; //-1 or 1
 const int16_t ecgChannel = ecgOn*(1+2*ppgOn)-1; //-1, 0, or 2
@@ -135,7 +139,7 @@
 //setup I2C, serial connection and timer
 InterruptIn intPin(interrupt_pin); //config p5 as interrupt
 I2C i2c(I2C_SDA,I2C_SCL);
-Serial pc(USBTX,USBRX,NULL,230400); //open serial port (optionally add device name and baud rate after specifying TX and RX pins)
+Serial pc(USBTX,USBRX,NULL,BaudRate); //open serial port (optionally add device name and baud rate after specifying TX and RX pins)
 
 
 //declare subroutines
@@ -218,7 +222,7 @@
     writeRegister(MAX86150_Addr,SystemControlReg,0x01); //chip reset
     wait_ms(2); //wait for chip to come back on line
     //if PPG or ETI are not enabled, then FIFO is setup for ECG
-    writeRegister(MAX86150_Addr,FIFOConfigReg,0x1F); // [4] FIFO_ROLLS_ON_FULL, clears with status read or FIFO_data read
+    writeRegister(MAX86150_Addr,FIFOConfigReg,0x7F); // [4] FIFO_ROLLS_ON_FULL, clears with status read or FIFO_data read, asserts only once
     uint16_t FIFOCode;
     FIFOCode = etiOn ? 0x000A : 0x0000 ; //ETI is last in FIFO
     FIFOCode = ecgOn ? (FIFOCode<<4 | 0x0009) : FIFOCode;  //insert ECG front of ETI in FIFO
@@ -256,16 +260,16 @@
 
 bool readFIFO(int numSamples, char *fifodata)
 {
-    char stat[1];
+//    char stat[1];
     bool dataValid = 0;
-    uint8_t tries = 0;
-    char newReadPointer;
-    clearInterrupts(stat);
+//    uint8_t tries = 0;
+//    char newReadPointer;
+//    clearInterrupts(stat);
     //get FIFO position
     readRegisters(MAX86150_Addr, FIFOReadPointerReg, i2cReadBuffer, 1); //you can do more sophisticated stuff looking for missed samples, but I'm keeping this lean and simple
     char readPointer = i2cReadBuffer[0];
-    while(!dataValid) {
-        tries++;
+//    while(!dataValid) {
+//        tries++;
         //try reading FIFO
         readRegisters(MAX86150_Addr, FIFODataReg, fifodata, bytes2Read); //get data
         //see if it worked if you are not servicing interrupts faster than the sample rate
@@ -283,7 +287,7 @@
 //        else {
 //            wait_us(100); //try again a moment later
 //        }
-    }
+//    }
     return dataValid;
 } //end readFIFO
 
@@ -362,7 +366,7 @@
 //    regDump(MAX86150_Addr,0xD0, 0xD0);
 //    writeRegister(MAX86150_Addr,0xFF,0x00);
     clearInterrupts(i2cReadBuffer);
-    i2c.frequency(maxi2cFreq);
+//    i2c.frequency(maxi2cFreq);
     //configure averaging
     if(ppgOn) {
         bits2Avg[rChannel]=ppgBits2Avg;