https://docs.mainsail.xyz/mainsailos/faq/serial-mcu-connection/
Serial MCU Connection (UART) - MainsailOS
Connect your printer's MCU to your SBC via UART serial on MainsailOS. UART is pre-configured and ready to use on supported boards.
serial mcu connectionuartmainsailos
https://docs.mainsail.xyz/mainsailos/supported-sbcs/orange-pi-zero-2/
Orange Pi Zero 2 - MainsailOS
Hardware reference for Orange Pi Zero 2 in MainsailOS — available UARTs, SPI, I2C buses, GPIO chip, and board-specific notes.
orange pi zeromainsailos
https://docs.mainsail.xyz/mainsailos/supported-sbcs/orange-pi-3-lts/
Orange Pi 3 LTS - MainsailOS
Hardware reference for Orange Pi 3 LTS in MainsailOS — available UARTs, SPI, I2C buses, GPIO chip, and board-specific notes.
orange piltsmainsailos