#include <Wire.h>
#include <MCP342X.h>

MCP3424 adc1(0x69);
MCP3424 adc2(0x68);

void setup() {

    SerialUSB.begin(57600);

    Wire.begin();

    adc1.generalCall(GC_RESET);

    adc1.creg[CH1].bits = { GAINx1, SR18B, ONE_SHOT, CH1, 1 };
    adc1.creg[CH2].bits = { GAINx1, SR18B, ONE_SHOT, CH2, 1 };
    adc1.creg[CH3].bits = { GAINx1, SR18B, ONE_SHOT, CH3, 1 };
    adc1.creg[CH4].bits = { GAINx1, SR18B, ONE_SHOT, CH4, 1 };
    
    adc2.creg[CH1].bits = { GAINx1, SR18B, ONE_SHOT, CH1, 1 };
    adc2.creg[CH2].bits = { GAINx1, SR18B, ONE_SHOT, CH2, 1 };

}

double value;
Channel active_ch = CH1;
bool blocking = false;

static char * errmsg[] = {"", "underflow", "overflow", "i2c", "in progress", "timeout"};

void loop() {

    ConvStatus error = adc1.read(active_ch, value, blocking);
    if (error == R_OK || error == R_OVERFLOW || error == R_UNDERFLOW) {
        if (error != R_OK) {
            SerialUSB.print("error: ");
            SerialUSB.print(error, DEC);
            if (active_ch == CH4) SerialUSB.println(" ");
            else SerialUSB.print(" ");
        } else {
            SerialUSB.print("CH");
            SerialUSB.print(1+active_ch, DEC);
            SerialUSB.print(": ");
            SerialUSB.print(value*1000, DEC);
            if (active_ch == CH4) SerialUSB.println(" mV");
            else SerialUSB.print(" mV ");
        }
        switch (active_ch) {
          case CH1: active_ch = CH2; break;
          case CH2: active_ch = CH3; break;
          case CH3: active_ch = CH4; break;
          case CH4: active_ch = CH1; break;
        }
        adc1.startNewConversion(active_ch);
    } else {
#if 0        
        SerialUSB.print("CH");
        SerialUSB.print(1+active_ch, DEC);
        SerialUSB.print(": ");
        SerialUSB.print("error: ");
        SerialUSB.println(errmsg[error]);
#endif        
    }
    asm volatile ("nop");
}