PS/2 Keyboard Serial Interface Module
Adding a full-sized keyboard can be a great idea for some projects, however there is some overhead with using interrupts and so on to scan the keyboard for keypresses. Instead, you can offload that processing work to this PS/2 keyboard serial interface module from PMD Way, with free delivery.
This PS/2 keyboard serial interface module uses an onboard microcontroller to read keypresses from a standard PS/2 keyboard and transmit the corresponding key values to external equipment via serial (UART), parallel, or I2C/TWI (selectable via jumper cap).
By offloading the keyboard decoding to this module, your main microcontroller (such as an Arduino) does not need to run a dedicated keyboard driver—it simply reads the processed key data directly.
How It Works:
- Keypress Detection: A pre-programmed MCU reads the PS/2 keyboard state. The status LED on the module flashes whenever a key is pressed.
- Simultaneous Output: Key values are output simultaneously via serial, parallel (D7–D0), and I2C/TWI.
- Example: Pressing the A key outputs the scan code 0x1C across both the serial interface and parallel pins D7–D0.
Key Release & State Signals:
- Outputs data on both keypress and key release ("pop-up").
- Features two dedicated status output pins: outputs TTL High (1) when any valid key is held down (except the Pause key) and returns to TTL Low (0) when released.
- I2C/TWI Jumper: If the I2C/TWI bus is not connected to a master device, you must remove the IIC/TWI Enable jumper cap; otherwise, the module will lock up and fail to function.
Important Usage Notes
- I2C/TWI Configuration: The module acts as an I2C master with a default address of 4.
- Jumper Requirement: Always remove the IIC/TWI Enable jumper cap when I2C is not in use.
- Serial Baud Rate: Set your host controller’s UART baud rate to 19200.
Don't forget to check out our full range of breakout boards if this doesn't meet your needs. And as always, all orders receive free delivery.
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