With this in mind, Adafruit devised a Pi plate that lets you control a 16x2 Character LCD, up to 3 backlight pins AND 5 keypad pins using only the two I2C pins on the R-Pi! The best part is you don't really lose those two pins either, since you can stick i2c-based sensors, RTCs, etc and have them share the I2C bus. This is a super slick way to add a display without all the wiring hassle.
This pi plate is perfect for when you want to build a stand-alone project with its own user interface. The 4 directional buttons plus select button allows basic control without having to attach a bulky computer.
The plate is designed for both Revision 1 and Revision 2 Raspberry Pi's. It uses the I2C (SDA/SCL) pins. We have a special extra-tall 26-pin header so the plate sits above the USB and Ethernet jacks.
This product comes as a kit! Included is a high quality PCB and all the components (buttons, header etc). A 16x2 Character LCD is included! Assembly is easy, even if you've never soldered before and the kit can be completed in 30 minutes. Check the product tutorial page for assembly instructions before purchasing.
Adafruit also has some handy Python code to help you easily talk to the LCD and buttons. You can also easily query the 5 keypad buttons to get input through the library, so you get extra buttons without using any more pins. The buttons are automatically de-bounced inside the library.
At this time, the code and plate can control the white backlight on or off. There is no support for PWM control of the backlight at this time, so if you need to have more granular control of the backlight, this plate can't do that (the I2C expander does not have PWM output).
- Dimensions: 2.2" x 3.35"
- Comes with a 16x2 RGB POSITIVE LCD
- Plug and play with any Raspberry Pi
- Uses only the I2C (SDA/SCL) pins