Hi.

Thanks for your previous help.

Is there any chance you could help with my question?

I am using P1-01AC+P1AM-100+P1-04RTD+PT1000 (channel one) and using the following code to read the temperature from the pt1000 sensor. It reports that there is no any sensor module connected to the first channel (it reads --328 'C for all of 4 channels). Could you please help me with that?

#include <Arduino.h>

#include <P1AM.h>

#include <SPI.h>

#include <SD.h>

const int SD_CS_PIN = SDCARD_SS_PIN; // SD card CS pin connected to P1AM slot 1 pin 4

const float VCC = 3.3; // supply voltage of the voltage divider circuit

const float VREF = 5.0; // reference voltage of the P1AM input module

const float R_REF = 1000.0; // reference resistor value for the voltage divider circuit

const float R_0 = 1000.0; // resistance of the PT1000 sensor at 0 degrees Celsius

const float A = 3.9083e-6; // constant A for PT1000 RTD

const float B = -5.775e-7; // constant B for PT1000 RTD

float temperature[4]; // array to store temperature readings

float resistance[4]; // array to store resistance calculations

unsigned long previousMillis = 0; // variable to store the last time a data point was collected

const unsigned long interval = 5000; // interval between data collection in milliseconds

const unsigned long duration = 100000; // duration of data collection in milliseconds

File myFile; // file object for writing to SD card

void setup() {

  Serial.begin(9600); // initialize serial communication at 9600 baud

  while (!P1.init()) {

    ; // wait for input module to initialize

  }

  pinMode(SD_CS_PIN, OUTPUT); // set SD card CS pin as output

  if (!SD.begin(SD_CS_PIN)) { // initialize SD card

    Serial.println("SD card initialization failed!");

    while (1); // stop program if initialization fails

  }

  myFile = SD.open("data.csv", FILE_WRITE); // open file for writing

  if (myFile) { // check if file opened successfully

    Serial.println("File opened for writing.");

  } else {

    Serial.println("Error opening file for writing!");

  }

}

void loop() {

  unsigned long currentMillis = millis(); // get the current time

  if (currentMillis - previousMillis >= interval) { // check if interval has elapsed

    previousMillis = currentMillis; // update previous time

    for (int i = 0; i < 4; i++) {

      temperature[i] = P1.readTemperature(1, i + 1); // read temperature from input channel i+1 in slot 1

      resistance[i] = (VCC * R_REF * temperature[i]) / (VREF * (VCC - temperature[i])); // calculate resistance using voltage divider circuit equation

      myFile.print(millis()); // write current time to file

      myFile.print(","); // separate time and temperature with comma

      myFile.print(i + 1); // write channel number to file

      myFile.print(",");

      myFile.println(temperature[i]); // write temperature to file and add newline character

      Serial.print("Channel "); // print a label for the temperature reading

      Serial.print(i + 1);

      Serial.print(": ");

      Serial.print(temperature[i]); // print the temperature value

      Serial.println(" degrees Celsius"); // print the unit of measurement for temperature

    }

  }

  if (currentMillis >= duration) { // check if duration has elapsed

    myFile.close(); // close file when program ends

    Serial.println("Data collection complete.");

    while (1); // stop program

  }

}