Any schematic for NodeMCU-M ?

[cefn]

Hi there,

I'm experiencing noise on the UART when powering and connecting to my NodeMCU-M boards using GNU screen or miniterm.py. This is not present when connecting to a NodeMCUv2 (ESP8266) running the same Micropython image.

See this product page...

http://www.vvdoit.com/new-nodemcu-m-development-board-based-on-esp-m2-from-esp8285-serial-wifi-wireless-module-compatible-with-nodemcu-diy-lua-iot-p1292428.html

I would like to investigate the schematic to understand if there may be an instability on powerup which introduces junk characters into the uart. Is there a reference schematic for the circuit available, please?