Adafruit RS-232 Full Pinout Level-Shifter Breakout

If you plan to interface with telco, retro, or industrial equipment, encountering RS-232 interfaces is possible. The Adafruit RS232 Full-Pinout Breakout offers 8 channels of UART to RS-232 level shifters, with 5 input and 3 output channels.

This reliable board employs the trusty MAX3243 from TI, part of the renowned MAX232 lineage, ensuring seamless functionality for all RS-232 requirements up to 250Kbps. It features a DE9-F female socket connector, designed specifically for easy device or cable connection.

RS-232, preceding USB, utilizes 9- or 25-pin D-Sub connectors for data transfer with flow control lines. Historically used for devices like mice, modems, and barcode scanners, it remains present in some modern devices.

For microcontroller or microcomputer communication with RS-232, a serial port/UART is necessary, coupled with a specialized level shifter to handle the +-6 to +-10V signals. The breakout board simplifies this process, providing a DE-9 connector for direct integration with devices.

Uniquely adaptable, it operates on 3.3V power and logic, deviating from older chips' capabilities. Supporting all 8 data pins, it facilitates full flow control signal utilization, including RTS, CTS, DTR, DSR, DCD, and RI.

The Valid line output offers a high logic level when detecting signal voltages, functioning as a 'connection made' indicator. Additionally, the Off pin can tri-state all pins via high logic from the microcontroller for power reduction.

This breakout arrives pre-assembled with a UART side for low-voltage power and logic levels, while the DE-9F RS-232 side manages high-voltage signals. Includes headers for quick soldering to a breadboard setup.