WT32-eth01 and DS18b20

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edstobi
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WT32-eth01 and DS18b20

#1 Post by edstobi » 27 Jan 2023, 00:42

Hello
I am using WT32-eth01 and am actually very satisfied with the modules.
Now I wanted to expand them with Environment - DS18b20. However, I have not found or read any documentation over GPIO only input.
I can get the temperature sensors to run on gpio 2, 4, 14 and 15, but not on 36, 39.
36 and 39 are marked only for input. Does the Environment - DS18b20 need in and output?
I am using build 20279 and/or 20116 and DS18b20 with a 4.7 k resistor https://espeasy.readthedocs.io/en/lates ... e-pictures and have all settings on default for the selected gpio
THX EDSTOBI

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Ath
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Re: WT32-eth01 and DS18b20

#2 Post by Ath » 27 Jan 2023, 07:36

The DS18b20 usually is connected using the 1-wire protocol, so that implies it needs an input/output pin, input-only won't work.

Those ETH enabled ESP32 units have only a limited number of GPIO's available, as the ETH unit uses quite a few already.
/Ton (PayPal.me)

TD-er
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Re: WT32-eth01 and DS18b20

#3 Post by TD-er » 27 Jan 2023, 08:30

It is best to refer to a build as either the build date, or even better the full filename as can be found on the sysinfo page.
It is also mentioned in the lower right corner of the web interface.
Or are you making your own builds and not using PlatformIO for this?

About what GPIO to use.
See this page of the documentation: https://espeasy.readthedocs.io/en/lates ... e-on-esp32

It shouldn't be possible to select "input only" pins for 1Wire protocol plugins.
At least not in builds made in the last ~2 years I guess :)

edstobi
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Re: WT32-eth01 and DS18b20

#4 Post by edstobi » 27 Jan 2023, 11:11

Thank you
This is the solution :!:
I had already thought of something similar, but I didn't know that reading and writing on a one wire is necessary.
I thought that only reading is done there

Ath wrote: 27 Jan 2023, 07:36 The DS18b20 usually is connected using the 1-wire protocol, so that implies it needs an input/output pin, input-only won't work.

Those ETH enabled ESP32 units have only a limited number of GPIO's available, as the ETH unit uses quite a few already.

edstobi
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Posts: 39
Joined: 28 May 2020, 20:33

Re: WT32-eth01 and DS18b20

#5 Post by edstobi » 27 Jan 2023, 11:25

TD-er wrote: 27 Jan 2023, 08:30 It is best to refer to a build as either the build date, or even better the full filename as can be found on the sysinfo page.

About what GPIO to use.
See this page of the documentation: https://espeasy.readthedocs.io/en/lates ... e-on-esp32
Thank you
To the used build: ESP_Easy_mega_20220427_test_A_ESP32_4M316k_ETH
and
ESP_Easy_mega_20221105_energy_ESP32_4M316k_ETH
best-pins-to-use-on-esp32
I know this valuable site and have also used it. I was not aware of the function of the one wire protocol that it requires reading and writing.


I only checked whether it could be the ESP or the build, but this was not the case.
TD-er wrote: 27 Jan 2023, 08:30 It shouldn't be possible to select "input only" pins for 1Wire protocol plugins.
At least not in builds made in the last ~2 years I guess :)
I can select it under Hardware, but it doesn't change anything. I learned that one-wire needs rx and tx on one wire.

Greetings
EDSTOBI

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