View Full Version : Need LCD and KEYPAD Help Thanx (PICS attached inside)

01-16-2007, 11:48 AM
hey guys i just got in my keypad and LCD FROM ALL ELCECTRONICS. The problem is that both items just have pinouts(15pins for the LCD) (·13pins for the keypad) with no built-in circuit. When i took an ELT class couple years back i remeber using an LCD with the SX chips, But the LCD only had three pins( a +5, serout, and gnd) which made it alot easier for programming and took up a lot less I/O.So what im pretty much asking s does anyone know where (website, etc.)·i can find the schematic in order to builld a on-board circuit for the keypad and lcd.

Chris Savage
01-16-2007, 12:18 PM
Information for connecting Parallel LCD Displays can be found on our website at the following link. I hope this helps. Take care.


Chris Savage
Parallax Tech Support

Bruce Bates
01-16-2007, 05:30 PM
No -

Here are a couple of driver IC's which will cut down the pin use immeasurably:

Keypad encoder -

LCD Controller -


Bruce Bates

<!--StartFragment -->

01-16-2007, 06:08 PM
Take a look at these two Nuts N Volts columns, I think they'll help you quite a bit.


Also, your post seems to ask how to convert your Parallel LCD to a Serial LCD.· There are chips that do this, but if you could program an SX you could use the SX as a co-processor to control the LCD and poll the keyboard.· Here are some links to other "backpacks":· (Disclaimer:· I haven't done business with any of these companies, I just wanted to give you an idea of what was out there.)

Scott Edwards electronics LCD backpack:·
SparkFun Electronics:· http://www.sparkfun.com/commerce/product_info.php?products_id=258
PH Anderson:· http://www.phanderson.com/lcd106/lcd107.html
Kronos Robotics:· http://www.kronosrobotics.com/xcart/customer/product.php?productid=16275&cat=292&page=1

Note:· Most of these require your LCD to be controlled by an·Hitatchi 44780 or clone.· They may not work with any other controller chip.· Please check your LCD before you order one of these.

This is a keypad to serial adapter:· http://www.solutions-cubed.com/solutions%20cubed/MEMKEY2003.htm

I could have sworn I've seen some all in one solutions, but I can't seem to find them at the moment.· Try some keyword searches.

Hope this helps!

01-20-2007, 11:22 AM
thanks guys