(baro) sensor offset calibration?

[espruino-discuss2]

Posted at 2023-02-18 by b3-4r

Hey, I've searched before posting but apologies in case I've missed anything. Yesterday I've noticed that the baro in my Bangle.js 2 is offset by about 30hPa from a Garmin GPS baro, a Casio watch baro and the local forecast and this is for the absolute measurement, not one corrected for altitude. Is there a way to calibrate this?

Thanks in advance!

[espruino-discuss2]

Posted at 2023-02-19 by user140377

ok interesting, both my Bangle.js 2 do read a value that is only +-1 hPa from comparable devices. I wonder if your Barometer reading hangs like in https://forum.espruino.com/comments/16642970/

Can you try the long-press-button-reboot. What pressure reading do you get afterwards?

To answer the question: I currently see no way to set an offset. But we can program that easily if needed.

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Posted at 2023-02-19 by b3-4r

Aw shucks, it does appear to be stuck at a value (tiny vario doesn't register a lift ride), baro app reads zero in digital and ~1000 analogue and multiple reboots don't change this.

I'll attempt shutdown, charging and stuff like that but for the moment it appears something is wrong with the baro itself :c

Thanks for the pointers!

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Posted at 2023-02-19 by Humpelstilzchen

Can you please try this: https://forum.espruino.com/comments/16645817/

If you have the SPL06 we might be able to reset the sensor without a full discharge:
https://forum.espruino.com/conversations/381706/#comment16770729

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Posted at 2023-02-19 by b3-4r

I've done both described procedures,

>[Bangle.barometerRd(0xD0),Bangle.barometerRd(0x0D)]
=[ 0, 16 ]
> 

and

Bangle.getPressure().then(d=>{
  console.log(d);
  // {temperature, pressure, altitude}
});
=Promise: {  }
undefined

I don't speak js in the slightest, no idea what to make of this so thanks for your help!

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Posted at 2023-02-19 by user140377

Looks like you got the SPL06, ok lets try a reset with

Bangle.barometerWr(0x0c, 9)

(at your own risk..) and a long-press-button-reboot afterwards. After that your barometer should work again.

As an alternative you can upload the attached file with the IDE as "baroreset.settings.js". Go to settings->app->baroreset and execute the reset. Also after a long-button-press reboot the barometer should work again.

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Attachments:

• baroreset.settings.js.txt

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Posted at 2023-02-19 by b3-4r

That helped! Thanks a lot. I've seen mentions of this happening due to the sensor being powered up long-term, in my case probably due to baro alarm widget so I'll try disabling that.

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Posted at 2023-02-20 by user140377

Good news!

baroalarm only turns on the barometer during a measurement. It gets powered off again.

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Posted at 2023-02-20 by @gfwilliams

That's interesting - do you think there's something we could do in the firmware to help fix this?

I didn't realise they would end up wandering off over time...

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Posted at 2023-02-20 by user140377

I don't believe it was wandering, I assume it just was stuck at that value. Happened to me multiple times.

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Posted at 2023-02-26 by b3-4r

Affirmative, that's what it turned out to be- stuck.