Q&A: 20x4 LCD with serial interface on Arduino Uno

Q:
Is there a way to connect multiple 20x4 lcd modules to an uno ... say...maybe up to 4 of them?

A:
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Arduino.cc has this example for a single serial LCD: http://playground.arduino.cc/Learning/SerialLCD

SparkFun has this example:
http://playground.arduino.cc/Learning/SparkFunSerLCD

The SparkFun example shows how to set up a serial connection over a specific single pin to an LCD, which means that the Uno can handle 4 of them in just 4 pins.
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Have you looked on sparkfun.com and adafruit.com for tutorials on 20x4 LCD displays?
Are you prepared to run a separate regulated power supply to the displays?
If the displays have a select pin that gets pulsed to load the byte/nibble on the data lines, then the answer is yes once you determine how you will multiplex the select pins.
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Try the Adafruit BackPack #292, you can change the I2C address and use up to 8 of them. You will need an additional power supply when you start using more displays.
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Thanks for the response....multiplexing the select pins....gonna get right on that....perfect for a noob.
A seperate power supply is no big deal...that's the easy part for me.
Adafruit has a tutorial but it really doesn't explain much about multiples except for adding some jumpers across the back for addressing purposes.....I still need to check the sparkfun page.
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from:http://www.element14.com/community/message/73216/l/20x4-lcd-with-serial-interface-on-arduino-uno#73216