RS-485 Shield for WeMos D1 Mini

March 21, 2023 |   |  Comment  |  ModBus, Wifi

RS-485 Shield for WeMos D1 is a half-duplex RS-485 to TTL Serial transceiver board for WeMos D1 Mini (ESP8266) and WeMos C3 Mini (ESP32) microcontrollers. This board was designed mainly for easy Wifi to Modbus connectivity using HomeAssistant‘s ESPHome Modbus Component.

Features

  • RS-485 chip: MaxLinear SP3485 or any other pin compatible RS-485 to TTL serial transceiver
  • RS-485 connector: RJ45 socket (TE / MOLEX) or 3.5mm 3-pin screw terminal
  • Supply voltage: 3.3V (from WeMos Mini microcontroller board)
  • Logic level: 3.3V
  • Serial interface connects directly to UART interface on the microcontroller (Serial debug should be disabled)
  • Esphome pins on WeMos D1 Mini (ESP8266) boards:
    • TX: 1
    • RX: 3
    • Flow control: 2
  • Esphome pins on WeMos C3 Mini (ESP32) boards:
    • TX: 21
    • RX: 20
    • Flow control: 6

Resources

Buy

  • Bare PCB: 3€
  • Pre-assembled: 12€
  • Pre-assembled with screw terminals: 17€
  • Pre-assembled with RJ45 socket: 17€

Triple Base for WeMos

August 20, 2021 |   |  Comment  |  Tools, Wifi

Triple base board for popular WeMos D1 (ESP8266) and WeMos S2 (ESP32) microcontroller boards and shields. Base board is designed for WeMos D1 boards but there is enough room on the sides to mount WeMos S2 with selected pin headers. There are prototyping areas between the double signal and power pins and rows of power pins (GND, 3.3V, 5V) on the bottom part of the board.

Features

  • Compatible with WeMos D1 (ESP8266) boards and shields
  • Partially compatible with WeMos S2 (ESP32) boards
  • Prototyping areas
  • Extra ground and power pins
  • Mounting holes
  • Headers are not included

Resources

Buy

  • Bare PCB: 5€