PS2 Keyboard Module

PS2 Keyboard Driver Module – Serial, UART, TWI/IIC, Parallel Output (Arduino AVR Compatible)

Overview

This PS2 keyboard driver module uses an onboard microcontroller to read keypress data from a standard PC PS2 keyboard and output the key values through multiple interfaces. It simplifies integration by eliminating the need for a keyboard driver in your main MCU system.

Key Features

• Converts PS2 protocol to:

  • TWI/IIC

  • UART (Serial)

  • Parallel interface

• Enhanced key state detection

• Supports simultaneous output via serial, parallel, and TWI/IIC

• Direct key data output without requiring additional driver development

• LED indicator flashes on key press

Applications

• Robotics

• Electronic products

• Microcontroller-based systems

Function Description

The module reads PS2 keyboard input using a programmed MCU and outputs key scan codes through selected interfaces. Output options can be configured using a short-circuit cap.

• Example:

  • Pressing the "A" key outputs:

    • Serial: 0x1c

    • Parallel (D7–D0): 0x1c

• TTL output behavior:

  • No key pressed: 0

  • Key pressed: 1

  • Returns to 0 after key release

  • Applies to all keys except the Pause key

Working Principle

• The MCU continuously reads PS2 keyboard key states

• On key press:

  • LED indicator flashes

  • Key data is transmitted via:

    • Serial communication

    • Parallel I/O

    • TWI/IIC (when enabled via short-circuit cap)

Important Notes

• TWI/IIC address: 4 (module operates as slave)

• Remove the “IIC/TWI enable” short-circuit cap if TWI/IIC is not used; otherwise, the module may not function properly

• UART baud rate: 19200

• If no device is connected to the IIC/TWI bus, the short-circuit cap must be removed

Specifications

Package Includes

• 1 × PS2 Keyboard Driver Module Serial Port Transmission Module