Hello!
I am pretty new to automation but I had some hardware classes at university and would like to play a bit with openhab. I was thinking to create my own temperature sensor, for that I assume I need a device capable to send information (Ideally something to flash with tasmota?) and a sensor to attach to it.
Can someone tell me if this is possible and which hardware will be good to do this as cheap as possible?
Thanks!
DS18B20 with ESP8266
I used NodeMCUs (an ESP8266 with the programmer built in) with DHT22s for just this project. I chose ESP Easy instead of Tasmota at the time because Tasmota required rebuilding the firmware to enable use of the analog pin and I wanted to also use a photoresistor. Tasmota now supports that though I think.
Another choice a lot of people use Wemos (much smaller but I think it requires a programmer to flash ESP8266).
An ESP32 would probably be way overkill and Arduino will be a lot more work and you’ll need some sort of shield to get it on the network (that’s what ESP8266s were created for in the first place before we discovered that they can run Arduino code natively).
The WemosD1 mini £2 or $3 on Ebay has a USB port
I was using NodeMCU, but have recently started using Wemos D1 Mini more - for a couple of sensors, it’s a little smaller, so easier to fit it into things.
I’ve got nearly 30 of them throughout the house, and they all run ESPEasy - it’s a case of plugging the device in, running the ESP.Easy.Flasher tool, selecting a couple of options, and away you go.
You can then configure it from a web browser.
Here’s the Devices page for the one in my garage - I’ve got a temp/humidity sensor (DHT22) plus a couple of magnetic door sensors. I also control a relay from one of the GPIO (General Purpose Input/Output) pins.
This talks via MQTT to my openHAB server, and feeds back the status of these devices, plus allows me to send the request to turn the relay on and off.
Thanks for the replies!
I was planning to power it with battery, still reading about using LiPo with a voltage regulator or a LiFePo4 and use the deep sleep of the ESP8266 to send the temp just once per minute or so. Because is battery powered I probably want to go directly for the ESP-01. Are my thoughts right?
ESP-01 does not have deepsleep by default, there is guide how to do it, but way more easier is just to use wemos d1 mini which has it already
Thanks didn’t know that but looking at it seems pretty simple just to connect the XPD_DCDC to the Reset, this guy here even removed the led! https://quadmeup.com/esp8266-esp-01-low-power-mode-run-it-for-months/ to save a bit more
yeah but you have to solder to chip pin direclty, which is super tiny … anyway yes, can be done
