Chief Delphi - Interfacing robot with LCD

Another way of using a LCD display with the Robot Controller is to use the digital pins. The digital pins can be configured to be outputs. Most LCDs have a 14 pin connector. If you use the LCD at is fully configurable and fastest state you will need to use 11 pins! The pins are DB0-DB7, E, R/W, RS.

Whoa that is too many, but this can be reduced. First the data lines (DB0-DB7) can be cut in half by doubling the number of commands sent to the LCD, which is ok. The R/W line can be connected to GND since we don’t really care about reading bytes back from the LCD. So now we are down to 6 digital lines. DB4, DB5, DB6, DB7, RS (register select), and E (enable).

We can even get it down further. If we use a 74164 serial shift register we can get the number of pins down to three.

Now, not only can we get down to a small amount of your digital pins, but the heavy lifting of designing and coding all of this has been done for you. The Seattle Robotics Society has a document about all of this. It can be found:
http://www.seattlerobotics.org/Works...vel2/index.php

The code is for a Atmel AVR processor, but with a little bit of work it can be translated for the RC.

If you use this and are at an event with team 1318, Issaquah High School, thank their mentor Cathy Saxton for this work.

-Jim