So while using the ESP8266 with OpenEVSE is not a new thing, I thought I'd share my recent tweak to my OpenEVSE box.
The clever flolk over at arduinos esp8266 section made esp8266avrisp so you can flash the board over wifi, and I hacked in a simple uart-tcp bridge giving me access to the serial port as well.
Picture attached shows a mains to 5v ac/dc converter the tiny Digistump Oak esp8266 and an arduino uno, all connected without level shifting, as it turns out the esp8266 gpio is 5v tolerant. (IMPORTANT: the esp8266 needs 3.3 supply, but the Oak handles this onboard!).
A 6 pin connector to the ICP port and 2 pin connector to the uart. Works as a charm so far. I will probably add 100ohm series resitors just to be on the safe side. But I was pleasantly surprised to learn about the 5v tolerance after strugling with a TXB0108 and the reset line, but at last no need!
Link to the avrisp code, and i flashed it from my computer directly to the esp IP address:
Code compiles and uploads in the Arduino IDE. Recommend looking for WeMos D1 mini modules as they are almost as compact as the Oak but a fraction of the cost. Or use a plain esp8266 module and a 3.3v supply directly (but then you need a uart to ttl cable to flash the esp).
No more opening the enclosure to program and fighting with the bluetooth serial link! Good times.
Bjørn Eikeland
So while using the ESP8266 with OpenEVSE is not a new thing, I thought I'd share my recent tweak to my OpenEVSE box.
The clever flolk over at arduinos esp8266 section made esp8266avrisp so you can flash the board over wifi, and I hacked in a simple uart-tcp bridge giving me access to the serial port as well.
Picture attached shows a mains to 5v ac/dc converter the tiny Digistump Oak esp8266 and an arduino uno, all connected without level shifting, as it turns out the esp8266 gpio is 5v tolerant. (IMPORTANT: the esp8266 needs 3.3 supply, but the Oak handles this onboard!).
A 6 pin connector to the ICP port and 2 pin connector to the uart. Works as a charm so far. I will probably add 100ohm series resitors just to be on the safe side. But I was pleasantly surprised to learn about the 5v tolerance after strugling with a TXB0108 and the reset line, but at last no need!
Link to the avrisp code, and i flashed it from my computer directly to the esp IP address:
Code compiles and uploads in the Arduino IDE. Recommend looking for WeMos D1 mini modules as they are almost as compact as the Oak but a fraction of the cost. Or use a plain esp8266 module and a 3.3v supply directly (but then you need a uart to ttl cable to flash the esp).
No more opening the enclosure to program and fighting with the bluetooth serial link! Good times.