meurig / esp-water-temp Goto Github PK

Currently the software is compiled with support for a ds18b20 (or similar) temperature sensor, but the hardware could interface with any sensor requiring +ve -ve and a sensor with a pull up resistor.

The obvious choice is a DHT22 temperature and humidity sensor (as I have one of these). Adding support for this could be as simple as compiling in the associated library and adding a lag parameter to the wifimanager page.

The device shouldn't post a temperature when it's unable to correctly read one from the sensor.

As of last night I added support for the DHT22 temp and humidity sensor in software. Since then I've been running one of my strip board modules with one of these sensors.

The at around 02:40 the module started posting 0's for temp and humidity. Resetting the device today seems to have fixed the problem.

The prototype appears to need a rest after power is pplied before it starts working. Not sure why that is, but it would be good if it simply booted cleanly!

Adding a watchdog might be a (pretty shoddy) way around it, as that should reset itself, but I'm not sure if it even boots to a stage where that would work.

Needs further investigation.

It would be good to add a watchdog to automatically reset the esp if it hangs.

Add a button (to the spare gpio?) that will allow the wifi settings and anything else set through the wifimanager to be reset.

It might be easiest to have this pin be read only on start up, so one might reset the device by booting it with the reset button held down.

As recommended by Andreas Spiess here:
https://www.youtube.com/watch?v=wf_msvWv1jk&list=PL3XBzmAj53Rlu3Byy_GkqG6b-nwEpWku0&index=21

It's worth putting a smoothing cap (1000uF) between the voltage regulator and the ESP8266.

This is a hardware modification rather than software, but I'm making a note here as it's something I'd like to do to my two stripboard prototypes - I'll close it once I've done it and taken a photo or two.

Currently the API key is hardcoded, this is unfortunate - it should be possible to use wifimanager to accept the API key as a parameter along with the wifi ssid and password.

How about two or three ds18b20 sensors all hooked up in parallel?

I think it would be easy to add headers for this and I think they support all running on the same bus. Not sure if you'd need a pull up resistor for each, but would be great if not!