When trying to flash the mainboard, the computer does not see the printer

The most common reasons are the following:

  • Wrong baudrate . Your computer may have selected a wrong baudrate such as 9600. The default baudrate for this printer is 115200.
  • Missing USB driver . Most of the time, the operating system installs the right USB driver for the printer. But sometimes, the installation fails. The i3 Plus printer uses a cheap USB-to-Serial bridge WCH CH340G. The driver can be downloaded from the web site of the manufacturer (in Chinese). The file to download is CH341SER.EXE for Windows and CH341SER_MAC.ZIP for macOS.
  • Bad USB cable . Try to use another, shorter, USB cable.