The RS-232 Expansion Card is a community-designed expansion card that adds a serial RS-232 port to any Framework laptop. Created by Josip Medved (medo64) and first published in May 2022, the card originally used a Microchip MCP2221 USB-to-UART bridge and a Texas Instruments MAX232 RS-232 transceiver. In November 2023, the design was reworked in KiCad to use an FTDI FT232R USB-to-serial bridge with a 5-pin connector and hardware flow control (RTS/CTS).
The RS-485 Expansion Card is a community-designed expansion card adding an RS-485 serial interface to any Framework laptop. Created by Josip Medved (medo64) and published in November 2022, it uses an FTDI FT232RL UART bridge with automatic transmit control and an SP485EN RS-485 transceiver, supporting baud rates up to 3 Mbaud.
The UART Expansion Card is a community-designed expansion card providing a USB-to-UART serial interface for any Framework laptop. Designed by Josh Cook (jyancat) of i2cLabs, it uses a CH340C bridge IC with switchable voltage and logic levels between 3.3 V and 5 V.