Simple interface to run my Anet A8 using ESP3D and an ESP-01 module. A TTL gate keeps startup serial data out of the printer. Requires removing 2 zero ohm resistors and installing a 6 pin header on the Anet controller in the BLE/USB position. You will also need to add code to the ESP3D sketch’s setup() function to set GPIO 0 as an output and write a logic LOW to that pin in order to enable transmit data to go out of the ESP-01 to the printer. This board should plug in to the connector next to the LCD connector. Power should be taken from the 12v board power (or a separate wall-wart might be used). Given the various problems an Anet A8 has, I didn’t want to stress its on-board voltage regulators with an ESP8266. This is revision 2 of this board, which uses a Recom R78E3.3-1.0 switching regulator. I also brought out GPIO2 to a header so the reset functionality of ESP3D can be used.

Schematic and board files (Eagle 7.x format) are at https://github.com/telanoc/anet_esp3d_board