Output always empty array

[DeckardCain2014]

Hi, I've cloned the most recent repo version and connected everything as shown in the Readme. However, it seems no value is received. This is my output and my connections:

sudo python -m mh_z19
{}

[UedaTakeyuki]

Hi DeckardCain2014,

Allways returning blank array without any error message nor stacktrace

It indicates that the sensor module didn't respond. Might be some hardware or cabling problem.

[DeckardCain2014]

Hi, thanks for getting back to me. Can you tell me what to check furthermore?

Am Do., 3. März 2022 um 00:07 Uhr schrieb Dr. Takeyuki Ueda < @.***>:

Hi DeckardCain2014,

Allways returning blank array without any error message nor stacktrace

It indicates that the sensor module didn't respond . Might be some hardware or cabling problem.

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[UedaTakeyuki]

I'm afraid I can't provide suitable advice. In general, cabling loosenes, electrify, and so on.

[DeckardCain2014]

Ok thanks

[to-roth]

Hi everyone, I had the same problem. In my case I forgot to enable the serial port hardware on my pi. Therefore always make sure that in your /boot/config.txt you have the following line:

enable_uart=1

or enable your serial port hardware just like described in the wiki (sudo raspi-config)

[hawtkey]

Hi, I had this error and found it to be that the Pi (3b+) uses UART for bluetooth and that can interfere with the co2 module. you can probably figure out a way to use a different channel if you need, but I disabled bluetooth since I don't use it:

simply add dtoverlay=disable-bt to the end of /boot/config.txt and reboot.

[resting-dove]

I had this error as well and after too much time I realised my pin connection was wrong. When i connected RxD <-> TxD and TxD <-> RxD (physical pins 8 and 10) as mentioned in https://github.com/UedaTakeyuki/mh-z19/issues/22#issue-688525199 I received measurements using serial as well.