Upgrading Firmware on old EmonEVSE


Bear with me as I’ve very little experience here. I inherited a fairly old EmonEVSE, running v5.1.0.T2 of OpenEVSE and v3.1.0.dev of WiFi firmware on an ESP8266 (though I’ve seen some posts saying this isn’t possible, see screenshots for my logic).

I’d like to get it upgraded to the latest firmware, and possibly upgrade the WiFi board if I have to. Can anyone give me some pointers on this? I’ve found this post so can follow the instructions around getting a USB programmer, but I’m not sure on firmware compatibility with the ESP8266.


You should have an ESP32, however before uploading new FW you should check inside your unit to determine which module you have, I think you will have Huzzah ESP32, but please check to be sure.

Assuming you have Huzzah ESP32 this is the FW file you should use to update: Success

Is it just a quirk/bug that it shows ESP8266 in the screenshot? I will open it up tomorrow to check.

I’ve confirmed I do in fact have a Huzzah ESP32.

As its running v3.1.0dev, am I safe to go straight to V7.1.3.EU of OpenEVSE, then upgrade the WiFi to v5? My ISP programmer is hopefully arriving tomorrow.

There’s no significant reason to update the OpenEVSE controller FW, I would leave this and just update the WiFi module.

On the firmware page it states below? I’m inclined to believe you as it seems you’re involved in the firmware dev, I’m just curious what it refers to!

NOTE: Breaking change! This release reccomends a minimum of 7.1.3 of the OpenEVSE firmware, features including Solar Divert and push button menus may not behave as expected on older firmware.

There are a few tweaks, but as far as I can remember it’s nothing major. I would upgrade the WiFi firmware first and then decide if you want to upgrade the EVSE firmware.

If you’re familiar with avr ISP uploading then updating the EVSE firmware is no problem, but for most users it’s not work the extra effort.