Multichannel Gas Sensor does not work on MKR GSM1400

Products & Technology Grove
#1

Hy,



Has anyone ever had a the Multichannel Gas Sensor (Grove) working on a MKR GSM1400?

When I download the “default” sketch for getting values, the sensor does not respond.

I have used it on a MKR Connector Carrier. That does not work. And also when I connect

it directly on the MKR Pins, without the carrier board, it does not work, giving no values back.



When I use the sensor on a Arduino MEGA, it works fine.



On the other hand, a SGP30 VOC Sensor board works on the MKR GSM1400.

So there is no connection problem, or using the wrong pinout.



Is there anyone who can help me?



thanks

Andy

#2

Hi There

I succeeded by the code below. :smiley:
[code]
#include <Wire.h>
#include “MutichannelGasSensor.h”

#define SENSOR_ADDR 0X04 // default to 0x04

void setup()
{
SerialUSB.begin(115200);
gas.begin(SENSOR_ADDR); //
}

void loop()
{
float R0_NH3, R0_CO, R0_NO2;
float Rs_NH3, Rs_CO, Rs_NO2;
float ratio_NH3, ratio_CO, ratio_NO2;

R0_NH3 = gas.getR0(0);
R0_CO  = gas.getR0(1);
R0_NO2 = gas.getR0(2);

Rs_NH3 = gas.getRs(0);
Rs_CO  = gas.getRs(1);
Rs_NO2 = gas.getRs(2);

ratio_NH3 = Rs_NH3/R0_NH3;
ratio_CO  = Rs_CO/R0_CO;
ratio_NO2 = Rs_NH3/R0_NO2;

SerialUSB.println("R0:");
SerialUSB.print(R0_NH3);
SerialUSB.print('\t');
SerialUSB.print(R0_CO);
SerialUSB.print('\t');
SerialUSB.println(R0_NO2);

SerialUSB.println("Rs:");
SerialUSB.print(Rs_NH3);
SerialUSB.print('\t');
SerialUSB.print(Rs_CO);
SerialUSB.print('\t');
SerialUSB.println(Rs_NO2);

SerialUSB.println("ratio:");
SerialUSB.print(ratio_NH3);
SerialUSB.print('\t');
SerialUSB.print(ratio_CO);
SerialUSB.print('\t');
SerialUSB.println(ratio_NO2);

SerialUSB.println("------------------------");
delay(1000);

}
[/code]
mabey it can help you

#3

Hy there,



thanks for your reply.

I tried your code and it works.

After a few try and error I found the solution:

In the default application (ReadSensorValue_Grove) of the library, there is the following setup;
</s><i> </i>void setup() { Serial.begin(115200); // start serial for output Serial.println("power on!"); gas.begin(0x04);//the default I2C address of the slave is 0x04 gas.powerOn(); Serial.print("Firmware Version = "); Serial.println(gas.getVersion()); } <e>

The problem is the call of the function gas.getVersion(). This seems to cause some errors.

Don’t know what kind of, but the function gas.measure_xxx(); always returns -1.

When commenting this or when I move the call to gas.powerOn() after this, it works fine.

Here is the modfied setup:
[code]
void setup()
{
SerialUSB.begin(115200); // start SerialUSB for output
SerialUSB.println(“power on!”);
gas.begin(SENSOR_ADDR);//the default I2C address of the slave is 0x04
SerialUSB.print("Firmware Version = ");
SerialUSB.println(gas.getVersion());
gas.powerOn();

}[/code]