A question about Keypads !!

[hassenman]

Hi all ,
i want to use a keypad with a microcontroller , what kind of keypads should i use , and where can i find them ?
can i for example use telephone keypads or they r diffrent ?
how many ports on the microcontroller will the keypad use ?
Regards .

 

[yogi]

ya u can u any keypad. See some ways to interface keypad with parallel port
**broken link removed**

u can use 74922 if you want to avoid keydebounce in keypads. See more about it in
**broken link removed**
**broken link removed**

Bibin John
www.bibinjohn.tk

 

[haytham]

you can build your own keybad with your preferred interface serial/parallel
It will give you good experience

Thanks
Haytham

 

[asmjager]

You can use one port (8bits) of you uController to produce your keypad. Make a Matrix contruction and multiply the number of lines by colluns used in design. This determine the maximun number of keys you can do with this ports.

Check the manufacturer application notes. I think everyone has one about thes subject.

Try this: **broken link removed**


Best regards,

 

[IanP]

Maybe instead of thinking about a keypad you should look at a PC keyboard ..
It is so easy to connect one to a microcontroller: all what you need is two microcontroller pins - one for DATA and one for CLOCK ..
Of course, you need to connect 0V and 5V to a keyboard, but it is like stating the obvious ..

Regards,
IanP

 

[hassenman]

Thanks for your replies guys , i think i'm gonna build my own , but IanP's idea is fascinating , DO u think IanP , that the 16F84 can handle it , and if yes , will the code writter to the controller be complicated ?
Regards .

 

[IanP]

Of course it can handle PC AT or PS/2 keyboards ..
Here is an example:
https://www.electronic-engineering.ch/microchip/projects/keyboard/v2xx/keyboard_v2xx.html

Regards,
IanP

 

[pic16f84]

you can use keypad with parallel port and using c langaue or vb its easy to program