4x4 Keypad and LCD sharing port B

[msnm4]

Hi all,

Could anybody give me some tips for the above subject?
I tested the 4x4 keyboard scan routine without problems and then tried to add the LCD to the same port putting E bit from lcd low during keyboard scan, but with no success.
The topology is:
a) 4 x 4 keypad using B0 to B7 for rows and cols
b) LCD using the 8 data bits on port B. E, R/W and RS inputs can be driven by port A or C.

Please, I need some hints, also to add a debouncing part por the key press.

Thx in advance

Mauricio

[duncan303]

Hi all,

I tested the 4x4 keyboard scan routine without problems and then tried to add the LCD to the same port ..... but with no success...........
Please, I need some hints,

Mauricio

Hi

Hint.... Can you get the LCD to work without the Keypad..? What did you have to change?

Duncan

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