support for si7012 i2c temp/hum sensor

[kroonen]

Hi,

I noticed that this project looks very good. I'm using nog some temp/humidity sensor with esp and lua with fhem software.

It should be bette to have it run with arduino , so this project looks very good.

Is there a way to get hardware support for the si7012.

lua examples : https://github.com/nodemcu/nodemcu-firm ... les/si7021

arduino library: https://forum.pjrc.com/threads/29237-Si ... or-Library

regards Richard

[Martinus]

Is there a way to get hardware support for the si7012.
regards Richard

I think this is possible, but I don't have one to test. I will order a few on eBay so we can have a look at this.

[Charly86]

Hi guys,

it's done, see http://www.esp8266.nu/forum/viewtopic.p ... 7021#p1265

[Ger]

I just received two chinese si7021 modules, with both modules I get a checksum error.
Are both modules corrupt or can it be an other problem?

[Ger]

I have tested the modules on an arduino mega 2560 with the following library https://forum.pjrc.com/attachment.php?s ... 1437698680
The example in this library is working correct

[Ger]

I have tested the modules on an arduino mega 2560 with the following library https://forum.pjrc.com/attachment.php?s ... 1437698680
The example in this library is working correct

[kroonen]

Hi,

I aslo tested with an si7021, that works ok with an esp8266 with lua. I also get these errors


Log

6939298 : HTTP : connection failed
6940323 : SI7021 : checksum error!
6940336 : SI7021 : Read Error!


regards richard

[Martinus]

I did not build this plugin, but I do have one of those devices. Didn't test it before, since I've guested that the plugin would just work.
I figured out that in my testlab, it also gets a read error with the default settings.
But if I change the resolution to 12 bit, it does work fine!

It works with 13 and 12 bits. It does NOT work with 14 and 11 bits. Strange.
Could you guys verify if your situations are similar to mine?

[Ger]

My results are the same as yours.

[kroonen]

Same results here.

[Martinus]

So the good news: There are at least two settings that can be used.
And the error seems consistent, so probably easier to reproduce and fix.
Maybe "Charly86" (the plugin developer) can have a look at the code?

[fluppie]

I have 2 HTU21D (should be software compatible) boards and they also don't work. Will try with the 13/12 bit setting.

[fluppie]

I have 2 HTU21D (should be software compatible) boards and they also don't work. Will try with the 13/12 bit setting.

DHT : Temperature: 23.90
DHT : Humidity: 52.50
SI7021 : Res=0x1 => Error 0x1
SI7021 : Read Error!
WD : Uptime 16 ConnectFailures 0 FreeMem 29296

DHT : Temperature: 23.70
DHT : Humidity: 52.50
SI7021 : checksum error!
SI7021 : Read Error!
WD : Uptime 1 ConnectFailures 0 FreeMem 27040

Still not working on 13/10 bits or 12/8 bits

[rmtucker]

Just thought i would mention here that i made some code changes to the si7021 code because it did not work on the htu21d module either.

Changed this:-

if (resolution == SI7021_RESOLUTION_11T_11RH)
delay(4);
else if (resolution == SI7021_RESOLUTION_12T_08RH)
delay(5);
else if (resolution == SI7021_RESOLUTION_13T_10RH)
delay(8);
else
delay(12);

Too
delay(55)

And it works faultlessly so i can assume it will work on the si7021 as well.

[dynode]

Came here from google, confirming this works for SI7021

[tozett]

may this thread now should be marked as SOLVED?

[pmayer]

Hi,

I can confirm that the SI7021 still won't work with R108 out of the box. Had to change the delay to 55 as mentioned.

Any chance this will get into the release?

cheers,
patrik

[Redfeather]

Hi,

I can confirm that the SI7021 still won't work with R108 out of the box. Had to change the delay to 55 as mentioned.

Any chance this will get into the release?

cheers,
patrik

For me the same, i have created a pull request for this issue https://github.com/ESP8266nu/ESPEasy/pull/44

[pmayer]

Great work!