Error trying to execute readMeasurement()

[AdmAreja]

Hello everyone,

I'm having a problem using this library with the arduino nano as shown in the image below:

Here is an exemple of the code:

#include <Arduino.h>
#include <SensirionI2CScd4x.h>
#include <Wire.h>

SensirionI2CScd4x scd4x;

void printUint16Hex(uint16_t value) {
    Serial.print(value < 4096 ? "0" : "");
    Serial.print(value < 256 ? "0" : "");
    Serial.print(value < 16 ? "0" : "");
    Serial.print(value, HEX);
}

void printSerialNumber(uint16_t serial0, uint16_t serial1, uint16_t serial2) {
    Serial.print("Serial: 0x");
    printUint16Hex(serial0);
    printUint16Hex(serial1);
    printUint16Hex(serial2);
    Serial.println();
}

void setup() {

    Serial.begin(115200);
    while (!Serial) {
        delay(100);
    }

    Wire.begin();

    uint16_t error;
    char errorMessage[256];

    scd4x.begin(Wire);

    // stop potentially previously started measurement
    error = scd4x.stopPeriodicMeasurement();
    if (error) {
        Serial.print("Error trying to execute stopPeriodicMeasurement(): ");
        errorToString(error, errorMessage, 256);
        Serial.println(errorMessage);
    }

    uint16_t serial0;
    uint16_t serial1;
    uint16_t serial2;
    error = scd4x.getSerialNumber(serial0, serial1, serial2);
    if (error) {
        Serial.print("Error trying to execute getSerialNumber(): ");
        errorToString(error, errorMessage, 256);
        Serial.println(errorMessage);
    } else {
        printSerialNumber(serial0, serial1, serial2);
    }

    // Start Measurement
    error = scd4x.startPeriodicMeasurement();
    if (error) {
        Serial.print("Error trying to execute startPeriodicMeasurement(): ");
        errorToString(error, errorMessage, 256);
        Serial.println(errorMessage);
    }

    Serial.println("Waiting for first measurement... (5 sec)");
}

void loop() {
    uint16_t error;
    char errorMessage[256];

    delay(100);

    // Read Measurement
    uint16_t co2 = 0;
    float temperature = 0.0f;
    float humidity = 0.0f;
    bool isDataReady = false;
    error = scd4x.getDataReadyStatus(isDataReady);
    if (error) {
        Serial.print("Error trying to execute getDataReadyFlag(): ");
        errorToString(error, errorMessage, 256);
        Serial.println(errorMessage);
        return;
    }
    if (!isDataReady) {
        return;
    }
    error = scd4x.readMeasurement(co2, temperature, humidity);
    if (error) {
        Serial.print("Error trying to execute readMeasurement(): ");
        errorToString(error, errorMessage, 256);
        Serial.println(errorMessage);
    } else if (co2 == 0) {
        Serial.println("Invalid sample detected, skipping.");
    } else {
        Serial.print("Co2:");
        Serial.print(co2);
        Serial.print("\t");
        Serial.print("Temperature:");
        Serial.print(temperature);
        Serial.print("\t");
        Serial.print("Humidity:");
        Serial.println(humidity);
    }
}

Can you help me ?

[LeonieFierz]

Hello @AdmAreja I assume you can read the sensor serial number? If not already the case, you can try to connect the the sensor to the 5V pin, as the 3V pin might not provide enough power.

[AdmAreja]

The sensor serial number should be printed on the sensor ? Because it's not there. The sensor was connected to the 5V pin already.

[LeonieFierz]

@AdmAreja the sensor serial should be read out during the setup() step of the sample code, so you can check if the wiring is ok. If so, you it might help to connect an external power supply to your Arduino Board, as the sensor needs ~200mA when taking a measurement.