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Strange jumps in MH-Z18B CO2 sensor values

alowhum Plugin Developer 5 Aug 2020, 09:39 last edited by alowhum 5 Aug 2020, 09:48

I have a MH-Z19B CO2 sensor (as part of the Candle system).

In the logs I see some strange sudden jumps between measured levels.

I don't think it's an issue with the code.

Could this be related to an internal re-calibration of the device somehow? Has anyone else seen something similar?

Or maybe the sensor is just dying?
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I've found that: char *protocolMyMessage2Serial(const MyMessage &message) { (void)snprintf_P(_fmtBuffer, (uint8_t)MY_GATEWAY_MAX_SEND_LENGTH, PSTR("%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%" PRIu8 ";%s\n"), message.getSender(), message.getSensor(), message.getCommand(), message.isEcho(), message.getType(), message.getString(_convBuffer)); return _fmtBuffer; } We put in the print "message.getEcho()", but this isn't echoed message. I think we should put "message.getRequestEcho()" here.
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Thanks for looking. What arduino ide version are you using and what version of mysensors?
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Strange jumps in MH-Z18B CO2 sensor values

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Strange jumps in MH-Z18B CO2 sensor values

Suggested Topics

Day 1 - Status report Announcements • 23 Mar 2014, 22:45 • hek 24 Mar 2014, 20:12

NODs stop responding, but ping works. Troubleshooting • 26 days ago • Marcin 26 days ago

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Raspberry Pi 5: invalid GPIO 9 Troubleshooting • 27 Aug 2024, 13:20 • igo 27 Aug 2024, 13:20

1Online

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Day 1 - Status report
Announcements • 23 Mar 2014, 22:45 • hek 24 Mar 2014, 20:12

NODs stop responding, but ping works.
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Echo request is not set
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Raspberry Pi 5: invalid GPIO 9
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Online

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