XENSIV PAS CO2 Communication error

[polstert]

Hello,

I have some communication errors with the Infineon XENSIV PAS CO2.

I can communicate with the sensor over I2C. Write to setting registers works and if I read them after for validation, the value is right. That all works until I will leave the idle mode.  Before entering the IDL Mode the status register (0x01) is 0x80, that means that everythin is ok.

If I write a 0x02 to the 0x04 register to begin continious mode, nothing happens and if I read the register after, the value is still 0x00. So I tried to start the single mode (write 0x01 to reg 0x04). After that the communication with the sensor is lost (sensor don't give me an ACK). So I have to unpower and power the sensor to communicate with him.

Unfortunately I haven't the USB eval board, because I'm a student and its too expensive for our project. So I can't test if the sensor is brocken.

[George_T]

Hi @polstert,

Since you are not using the evaluation board, I strongly recommend to refer the thread below:

https://community.infineon.com/t5/CO-sensor/CO2-value-read-by-Sensor2Go-Kit-is-different-than-CO2-va...

Connect the capacitors in the power supply lines as given in the option 1 (also in datasheet, section 4.3.1, figure:6). 

Please let me know if you are still facing the issue.

Thanks and regards,

George

[George_T · Accepted solution]

Hi @polstert,

If you are using Arduino board, please refer to Arduino library for CO2 sensor. 

Refer to the Programming guide for XENSIV PAS CO2 for more information on communicating with the sensor board.

Could you please let me know which controller is used?

In the current sequence, which is shared, please provide a delay of at least 100 milliseconds after setting to continuous mode and read the register. Please keep appropriate delay in the measurement loop as per the measurement rate.

Please let me know if this solves the issue.

Thanks and regards,

George