Simple Keypad Interface

Xnient

Hi,

I am very new to the BASIC Stamp and electronics in general. I just started my first year of electrical engineering, and I have decided to pursue a few projects of my own. First off I would like to say that this is a very helpfull community and has helped me many times now, but I cannot find anything to help me with my latest challenge.

I have a 4x3 Standard Matrix Keypad (http://rocky.digikey.com/scripts/ProductInfo.dll?Site=CA&V=136&M=96AB2-102-R) and I am having trouble reading key inputs. I do not realy want to use an encoder/decoder, unless I absolutely have to. As of now I have tried many different method of reading the keypresses with no avail.

Does anyone have some helpfull hints that can get an aspiring student on his feet in this matter?

Is there a way to read the key presses without an encoder or decoder? I thought of using RCTIME, but that would require a Smile load of capacitors. I also tried setting, for instnace, PIN 1 to high and trying to detect which other PIN is high by using IN# = 1, but that didnt work either.


Thanks alot,


-Jon

Forrest

Nuts and Volts Column 22, which you can download here www.parallax.com/html_pages/downloads/nvcolumns/Nuts_Volts_Download_V1.asp has all the information you need for connecting and reading that keypad.

Xnient

Thank you so much, after a few tries, I finally got it working!


You guys/girls are great!~

Don

There is an application note at http://www.zbasic.net/appNotes·that describes a way to interface a keyboard·using only a few I/O lines.· The ideas could easily be applied to the Stamp.

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Don Kinzer

ZBasic Microcontrollers
http://www.zbasic.net
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