The serial LCD board interfaces any HD44780-based LCD (this is the vast majority of LCDs you will encounter), with a three-wire serial interface, consisting of +5 volts, ground, and serial data. The board uses a programmed PIC chip, created by the late Maryland EE professor Peter Anderson, to convert serial commands, e.g. Serial.print(“Modern Device”), into LCD text.
Peter Anderson’s command set is very robust and complete, with commands to control the backlight and address 8 custom characters that are available for user interfaces.
I programmed a custom character generator, for doing the slightly confusing math necessary to generate custom characters, which is also available below.
I guess there needs to be a caveat in here. The kit will accommodate the vast majority of LCDs. There are a number of pinouts, which are thankfully very rare, that require remapping the pins. Mostly this involves the backlight pins, which for some reason are (rarely) found on the pin 1 end of the data pins instead of the pin 14 end, which is vastly more common, and is the way that the kit is laid out. It is a good idea to confirm the pinout of your LCD with the pinout listed in the instructions before plugging it in. If you can’t get the datasheet however to the display however, just plug it in and try it, the overwhelming odds are that it will work fine.
This kit includes all the parts needed to build the LCD serial board. The kit also includes a handy three conductor cable to hook up the display to the driver board. We offer these kits in three baud rates 2400, 9600 and 19200 baud. 2400 baud chips will be useful for PICAXE and some Basic Stamp users.
The programmed PIC chip alone is available, for chip replacement or those wanting to build their own boards.
- three-wire interface (5V, GND and serial data)
- 1×16 & 2×8 headers to interface the overwhelming majority of LCDs
- robust command set, including software control
- three unused pins are brought out to pads, and are under software control as general purpose
- 1 LCD 117 Serial to LCD printed circuit board
- 1 LCD 107 / 117 programmed 18 pin PIC chip (Default: 9600)
- 1 TIP120 NPN transistor
- 1 400x diode for reverse polarity protection
- 1 .1 ufd (104) 25 volt monolithic ceramic capacitor
- 1 10 k ohm 1/4 watt resistor (brown-blk-orange)
- 1 1k ohm 1/4 watt resistor (orange-orange-brown)
- 1 5 k ohm trimpot for LCD contrast control
- 1 27 ohm 1/4 watt resistor (red-violet-black) (optional use)
- 1 15 ohm 1/4 watt resistor (brown-green-black) (optional use)
- 2 momentary switches
- 1 16 position male header pins
- 1 16 position female header pins
- 1 2 x 8 position female header pins
- 1 3 position right-angle male header pins
- 1 12″ three conductor cable with two female ends (servo style cable)
- LCD117 Kit (requires soldering iron to attach through-hole components)
- 5V 20×4 Character LCD Datasheet
- 5V 16×2 character LCD datasheetNote that the first 2 pins on the datasheet are labelled incorrectly. Pin 1 should be ground and pin 2 should be VCC. The manufacturer configures the same display differently in some cases.
- LCD117 Command Summary (pdf)
- LCD117 command summary (MS Word)
- LCD117 LCD Kit Instructions NOTE: We have swapped the resistor on the TIP120 NPN Transistor from 330 ohm to 1k ohm.
- LCD Demo for the Arduino language
- LCD Custom Character Generator