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Serial Pi (Discontinued)

Serial Pi RS232 Expansion board

Serial Pi on a white background

This item has been replaced with the Serial Pi Plus and Serial Pi Zero

Go to the Serial Pi Plus.

Go to the Serial Pi Zero.

  • RS232 Master Port.
  • Control the Raspberry Pi over RS232 or connect to external serial accessories.
  • Stackable with other Raspberry Pi accessory boards.
  • Mounting hole for use with the AB Electronics UK mounting kit (sold separately)

The Serial Pi is a communication board supporting the RS232 serial protocol.

Please note that you can only use one Serial Pi board on a Raspberry Pi.


The RS232 port is connected to the UART port on the Raspberry Pi using a MAX3232 interface. The MAX3232 IC converts the 3.3V UART port to RS232 voltages, allowing communication with RS232 compatible devices over a DB9 serial cable. Using a null-modem cable, the board allows terminal access with Linux on the Raspberry Pi using a terminal application. The RS232 port can be accessed through the DB9 port or the solder points on the PCB.

An array of 2.54mm pitch holes with 3.3V and 5V connections are also provided on the PCB, allowing you to build additional circuits on the board.


Serial Pi Datasheet


Click to View
Click to View the schematic PDF.

Mechanical Drawings

Click the image to enlarge

Sample Code & Tutorials

Configuring the RS232 communication on the Raspberry Pi

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Created 11/05/2016 | Last Updated: 04/07/2024

Related Expansion Boards

Order a Serial Pi Plus Photo of Serial Pi Plus
Serial Pi Plus

RS232 Serial Port for the Raspberry Pi

£13.19 Ex VAT: £10.99
Order a Serial Pi Zero Photo of Serial Pi Zero
Serial Pi Zero

RS232 serial interface for the Raspberry Pi Zero

£11.39 Ex VAT: £9.49

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