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.
|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:
|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|