No readable output from Sensor about arduino-mq131-driver

[ostaquet]

Hi Chris,
Seems strange... The line Calibration in progress... is in the main function and should be followed by the Calibration done! in the example. The calibrate() method doesn't output anything so I don't understand why you get the ?F?.

• Which Arduino board are you using?
• Did you check the sensor with a multimeter?
• Did you change something in the code?

KR,
Olivier

[CAMR94]

Hi Oliver,

Thank you for the reply.

I did not change anything in the Code:

I'm using a Sainsmart Knockoff of the Arduino Uno.

By now I actually don't even get the Calibration in Progress message. Only the weird ?F?.

I checked the circuit. The Heater circuit is getting 6.5V and the Sensor circuit 3.5V

Greetings, Chris

[ostaquet]

Hi Cris,
Did you configure correctly the baud rate of the serial debug interface?
In the sketch embedded in the example, the serial is configured at 115200bps.
KR,
Olivier

[CAMR94]

Hello Oliver,
You were right, the Baud rate was wrong. Thank you very much.
I am now running it at 9600bps and I'm getting a reasonable output. But the Sensor shows a saturation of "inf ppm" etc. so every value is at infinity. But I had no time yet to let it burn in, so I guess I will do that next.

Again thank you very much.
Greetings,
Chris