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maarten-pennings / CCS811

Arduino library for the CCS811 gas sensor for monitoring indoor air quality.
MIT License
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Error Code - More questions... #18

Closed delsol25 closed 5 years ago

delsol25 commented 5 years ago

Hello Maarten, First, many thanks for your code, this is really appreciated. I'm not able to get any value out of my CCS811. First I upgraded the application to 2.0 using your code. It work without any problem. Here is what I'm getting:

setup: Starting CCS811 basic demo setup: ccs811 lib version: 10 setup: hardware version: 12 setup: bootloader version: 1000 setup: application version: 2000 CCS811: waiting for (new) data CCS811: errstat=2091=--VhxmrwF--Ad-iE CCS811: errstat=2091=--VhxmrwF--Ad-iE CCS811: errstat=2891=--VhXmrwF--Ad-iE CCS811: errstat=2899=--VhXmrwF--AD-iE CCS811: errstat=2899=--VhXmrwF--AD-iE CCS811: errstat=2899=--VhXmrwF--AD-iE CCS811: errstat=2899=--VhXmrwF--AD-iE

I updated to the latest ESP8266 Library. I'm using a China D1 Mini Supply is maybe a little low 3.27 since i'm powering with the USB. Wake pin is tie to GND.

Waiting for your feedback David

delsol25 commented 5 years ago

Hello again, Really sorry to distrub, I think I just got a bad sensor. I tested with another one and everything is fine. I also updated the firmware . 2 on 2. Thanks

maarten-pennings commented 5 years ago

As you can see in the .h file ERRSTAT is a merge of two hardware registers: ERROR_ID (bits 15-8) and STATUS (bits 7-0)

So, we have to split the hex value 2899 and the string (--VhXmrwF--AD-iE). ERROR has hex value 28 which corresponds to --VhXmrw and STATUS has hex value 99 which corresponds to F--AD-iE Capitals mean bit-is-set, lowercase means bit-is-clear, dash means bit has no meaning. See function CCS811::errstat_str for details

What does this mean?

Most part of STATUS is ok (see datasheet page 18 on ams.com/ccs811): The F tells that the firmware is in application mode (not bootmode) , the A means that the application image is valid (flashed correctly), D means there is new measurement data. But you also have an E - for Error. This should not happen.

When you have an E/error, the ERROR register gives details. You have V and X (datasheet page 24); X meaning "The sensor resistance measurement has reached or exceeded the maximum range". I'm not sure what does means, maybe your sensor is indeed broken.

maarten-pennings commented 5 years ago

If you are happy, you can close the issue.