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Programming keypad 4x4 using encoder 16 key on STM32VL

marouenebrikcha
Associate II
Posted on March 19, 2012 at 14:01

Heelo

I' using microcontroller STM32VL Discovery and i won't to interface caracter of keypad 16 key on LCD using an encoder 16 keys .

Please help me friend's !! 
6 REPLIES 6
Posted on March 19, 2012 at 15:09

Wouldn't you just hook up the row/column to GPIO pins and scan it like every other implementation?

A quick Google should manifest a whole slew of examples

http://www.atmel.com/Images/doc2669.pdf

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emalund
Associate III
Posted on March 19, 2012 at 15:44

I almost made a boo-boo once by routinely making the outputs to the keypad push-pull. That would make beautiful blue smoke come out of the chip if you press two keys at the same time. Fortunately, I caught it before loading the code into the micro.

I can see someone making the same mistake by routine, thus this post.

Erik

emalund
Associate III
Posted on March 19, 2012 at 15:51

WOW, just had a peek at your Arghmel link and, lo and behold, they make that very mistake:

 ''Rows are connected to four PIO pins configured as outputs.''

Erik

emalund
Associate III
Posted on March 19, 2012 at 15:51

WOW, just had a peek at your Arghmel link and, lo and behold, they make that very mistake:

 ''Rows are connected to four PIO pins configured as outputs.''

Erik

marouenebrikcha
Associate II
Posted on March 19, 2012 at 22:26

marouenebrikcha
Associate II
Posted on March 19, 2012 at 22:29