File content as of revision 28:13f78b4a23c3:

#include "mbed.h"
#include "ADS8568_ADC.h"
#include "FastPWM.h"
#include "MODSERIAL.h"

#define MEAS_DELAY         60  // measurement delay after turning on FET (us)
#define LOG_INTERVAL     1000  // log file interval (ms)
#define START_DELAY      1000  // pause for startup (ms)
#define N_STEPS           100
#define BUFFER_SIZE      4096
#define PWM_PERIOD_TICKS 1000 

//UID lookup address and pointer
#define UID_ADDR 0x1FFF7A10
unsigned long *uid = (unsigned long *) UID_ADDR; 

//UID and drive board calibration table
#define UID_TABLE_LENGTH 4

int drive_board_serial_number[UID_TABLE_LENGTH] =
  {1,
   2,
   3,
   4};

unsigned long drive_board_uid[UID_TABLE_LENGTH][3] =
 {{0x005B0060, 0x32375101, 0x32363531},
  {0x00530028, 0x32375116, 0x30333732}, // updated board 2 UID was  {0x0051003D, 0x32375114, 0x30333732},
  {0x00520060, 0x32375101, 0x32363531},
  {0x00570060, 0x32375101, 0x32363531}};

float drive_board_cal[UID_TABLE_LENGTH][2][2] = 
 {{{0.0908347476278717, 10.1921343711427}, {0.0497613470164513, 10.2109327517567}},
  {{0.0596907336847412, 10.1550084867437}, {0.0320376283698263, 10.2580153464834}},
  {{0.0119648730956925, 10.4065902688349}, {0.0256785142683800, 10.2921134395920}},
  {{0.0482969653247984, 10.0688110602909}, {0.0882102280729402, 10.1322703041679}}};
  
MODSERIAL pc(PA_9, PA_10, BUFFER_SIZE); //mcu TX, RX, BUFFER_SIZE byte TX and RX buffers
ADS8568_ADC adc(PB_15, PB_14, PB_13, PB_12, PC_15, PC_0, PC_1, PC_2, PC_3);
I2C i2c(PB_7, PB_8);            //SDA, SCL
Timer timer;
DigitalIn adc_busy(PA_8);                   //Busy interrupt sig#

//Heater Control
FastPWM drive_1(PC_9);
FastPWM drive_2(PC_8);
FastPWM guard_1(PC_7);
FastPWM guard_2(PC_6);

//Indicator LEDs
DigitalOut hb_led(PC_13);       //Green
DigitalOut led_0(PC_4);         //Red
DigitalOut led_1(PC_5);         //Green

//User buttons
DigitalIn user_0(PB_0);
DigitalIn user_1(PB_1);

BusOut converts(PC_0, PC_1, PC_2, PC_3);

int main() {
    int eTime;
    int v[2], curr[2];
    double r_adc[2], r_ohm[2];

    int i_port[2] = {0,2};
    int v_port[2] = {1,3};
     
    pc.baud(115200);
    adc.init();
    
    // Initialsation - all heaters off
    drive_1.prescaler(1);
    drive_1.period_ticks(PWM_PERIOD_TICKS);
    drive_1.pulsewidth_ticks(0);

    guard_1.prescaler(1);
    guard_1.period_ticks(PWM_PERIOD_TICKS);
    guard_1.pulsewidth_ticks(0);

    drive_2.prescaler(1);
    drive_2.period_ticks(PWM_PERIOD_TICKS);
    drive_2.pulsewidth_ticks(0);

    guard_2.prescaler(1);
    guard_2.period_ticks(PWM_PERIOD_TICKS);
    guard_2.pulsewidth_ticks(0);
   
    pc.printf("\r\nUnique ID: %08X %08X %08X \r\n", uid[0], uid[1], uid[2]);   
    int i_board = -1;  
    for (int i = 0; i < UID_TABLE_LENGTH; i++)
    {
      if (uid[0]==drive_board_uid[i][0] && uid[1]==drive_board_uid[i][1] && uid[2]==drive_board_uid[i][2])
        {
            i_board = i;
            i = UID_TABLE_LENGTH;
        }
    }
    
    if (i_board != -1) pc.printf("Drive board: Board %d   ADC measurement: PWM heater pulse, 60us delay\n",drive_board_serial_number[i_board]);
    else pc.printf("Drive board UID match not found\n");

    pc.printf("iStep,      eTime,        I1,         V1,     R1_adc,     R1_ohm,       I2,         V2,     R2_adc,     R2_ohm\n");
    
    wait_ms(START_DELAY);
    timer.start();

    // indicate start
    led_0 = 0;
    led_1 = 1;
    
    for (int iStep=0; iStep<N_STEPS; iStep++) {

        eTime = timer.read_ms();
    
        for (int iHeater=0; iHeater <2; iHeater++) {
            // measure heater
            if (iHeater==0) 
                drive_1.pulsewidth_ticks(PWM_PERIOD_TICKS);
            else
                drive_2.pulsewidth_ticks(PWM_PERIOD_TICKS);
            wait_us(MEAS_DELAY);
        
            //Start ADC conversion
            adc.start_conversion(15);

            //Wait until ADC is free
            while(adc_busy == 1) {
                wait_us(1);
            }

            //Turn off heater
            if (iHeater==0)
                drive_1.pulsewidth_ticks(0);
            else
                drive_2.pulsewidth_ticks(0);
                
            wait_us(MEAS_DELAY);
        
            //Get ADC values
            adc.read_channels();
            curr[iHeater] = adc.read_channel_result(i_port[iHeater]);
            v[iHeater] = adc.read_channel_result(v_port[iHeater]);
            r_adc[iHeater] = (float)v[iHeater]/(float)curr[iHeater];
            if (i_board != -1)
                r_ohm[iHeater] = drive_board_cal[i_board][iHeater][0] + r_adc[iHeater]*drive_board_cal[i_board][iHeater][1];
            else
                r_ohm[iHeater] = 0.0;
                
            //Wait before drivinng other heater
            wait_ms(LOG_INTERVAL/2);

        }
        //Write output for iHeater
        pc.printf("%5d, %10d, %10d, %10d, %10.6f, %10.6f, %10d, %10d, %10.6f, %10.6f \n", iStep, eTime, curr[0], v[0], r_adc[0], r_ohm[0], curr[1], v[1], r_adc[1], r_ohm[1]);
        
    }
    
    // indicate stop
    led_0 = 1;
    led_1 = 0;

 }