Node MCU who provides the LUA firmware also propose evaluation boards: http://nodemcu.com/index_en.html#fr_54747661d775ef1a3600009e
An Arduino + ESP-01 board, with an ATMega 644: http://rayshobby.net/cart/esptoy
ATMega 644 has two hardware serial ports
ESP8266-EVB is Evaluation board for ESP8266 with relay, button, UEXT, all GPIOs available on 0.1“ header https://www.olimex.com/Products/Modules/Ethernet/ESP8266-EVB/open-source-hardware
The AI-Thinker board is an evaluation board with an onboard STC15L204EA microcontroller along with a relay, buttons and LEDs on all GPIOs, a relay, a buzzer, LDR, a socket for NRF240 modules, CH340 USB to Serial converter and DIP switches allowing different IO routing configurations to be setup. A small adapter board connects the normal ESP8266 modules to a pair of 2×4 headers. The board is widely available from a number of Chinese vendors.
This is the left-most switch when the USB port is at top. Controls routing of the serial data lines.
No. | Label | Function |
1 | DCRON | ON=Connect ESP TX line to MCU RX line. |
2 | DCTON | ON=Connect ESP RX line to MCU TX line. |
3 | ESPTON | ON=Connect ESP TX line to CH340. |
4 | MCUTON | ON=Connect MCU TX line to CH340. |
5 | ESPRON | ON=Connect ESP RX line to CH340. |
6 | MCU_R_ON | ON=Connect MCU RX line to CH340. |
So, to achieve the following standard configurations set the dip switch as follows:
Configuration | 1 | 2 | 3 | 4 | 5 | 6 |
MCU connected to CH340 | OFF | OFF | OFF | ON | OFF | ON |
ESP8266 connected to CH340 | OFF | OFF | ON | OFF | ON | OFF |
MCU connected to ESP8266 | ON | ON | OFF | OFF | OFF | OFF |
This is the right-most switch when the USB port is at top. Controls routing of some of the IO and signal lines.
No. | Label | Function |
1 | GPIO14 | ? |
2 | DLMCU | ? | | 3 | CHPDH | ON=Enable pull up on CHPD line of ESP8266. | |
4 | GPIO0H | ? | | 5 | GPIO15H | ? |
6 | GPIO2_H | ? |