USB HID to UART, RS-485 Extension Board

https://www.electrodragon.com/product/usb-hid-to-uart-rs-485-extension-board/

  • 5V/GND external power supply
  • blue box: chip output to USB
  • red box: chip output to RS485

Pin Definitions:

  • Left-top USB: USB-TTL data
  • Left-bottom Pins: RS-485
  • right-top USB: USB Down
  • right-bottom USB: USB UP

check points

  • RS485 no output?
    • please check if the jumper is set to red box
    • USB and RS485 output can not be selected in the same time.

SCH

  • SCH1 of chip

  • SCH2 peripheral

Configuration

Default baud rate is 115200

S1 / S0 - 1/0 default

  • 11 = mode 1
  • 10 = mode 2
  • 01 = mode 3
  • 00 = mode 4

baud1 / baud 0 - 115200 baudrate default

  • 11 = 115200 baudrate default
  • 01 = 57600
  • 10 = 38400
  • 00 = 300 000

SEL

  • 1 = master mode, upper machine mode, USB to PC machine
  • 0 = slave mode, accpet USB devices like keyboard, mouse

demo

https://www.youtube.com/shorts/UZahFdell4g

ref