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Moderator: eriksl

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By eriksl
#84130 ... and fourth: bmp280. I bought a few some months ago. Could not get them working. Air pressure was always some random fixed (wrong) value, all of them. But the bmp280's I already had worked fine with the same code. So I ordered some more and they do actually work like expected. Anyone an idea? Fakes?
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By davydnorris
eriksl wrote:First one: ccs118 gives max value continuously after a few days on. I have it running in "continuous" mode and there are no errors. After a reset, the readings go back to normal.

I am not using the baseline save or temperature/humidity correction, because both temperature and humidity are quite constant here.

There was a post on a semi related topic and it referenced a thread that looks interesting:

Check out the CCS811 data graph - it's exactly as you describe. The problem was tracked to an I2C clock stretch that was too low, set by the code on a different sensor.

I've never seen the problem you describe, mainly because I deep sleep a lot, but also because I have clock stretch set very high
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By eriksl
#84158 Thanks for your interest. I read the link, but since they're talking about "Core" and "Wire" it suggests they're using arduino - I am definitely not. I have my own i2c implementation that is very, very resillient and manages to reliably talk to even the most broken (i2c-wise) sensors. There are no i2c errors, at all. It's just that the value returned is nonsense. So I guess it's another issue altogether.
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By StanJ
#84518 I've been running a BME280 continuously in 'forced' mode since July, one sample every 30 minutes. No problems after I filtered out the bad boards. Stock Wemos D1 Mini and the Arduino IDE.

I had problems early on: some of the boards out of China may have 'clone' parts on them that either didn't work, or didn't follow the Bosch specs. 3 boards wouldn't even ACK their address, so I kept testing until I found a few boards that worked OK. The metal can on the sensor doesn't look like the Bosch pictures, which is why I presume they're no-name clone parts. Initially I thought the three non-functional boards had the parts soldered on backwards, as the hole in the can was on the other end of the can compared to the Bosch datasheet.

I never did get my BME680 board: the US Post Office lost it. I didn't bother trying to get a replacement.