Adafruit RS232 Pal - Two Channel UART to RS-232 Level Shifters

If you're looking to interface with telco, retro, or industrial equipment, you'll probably encounter RS-232 interfaces. The Adafruit RS232 Pal provides two duplex channels of level shifting, managing high/negative voltage generation in a cost-effective breakout board.

This device features the reliable MAX3232E chip, part of the classic MAX232 lineage, ensuring flawless operation for all RS-232 applications up to 250Kbps. RS-232 was commonly used before USB, with 9 or 25 pin D-Sub connectors for data and flow control lines, connecting devices like mice, modems, barcode scanners, and teletypes.

The RS232 Pal makes it easy to connect a microcontroller or microcomputer to RS-232 devices by providing the necessary level shifting. While most UARTs operate at 0-3.3V or 0-5V logic level, RS-232 requires ±6 to ±10V, necessitating a specialized shifter for correct voltage conversion. This board eliminates the need to manually wire up additional capacitors.

Running on 3.3V power and logic, the board is compatible with both RX and TX channels and two flow control pins like RTS and CTS. Fully assembled, it includes UART and RS-232 high voltage sides with doubled and negative voltage rails for easy referencing, along with headers for quick breadboard soldering.