>     as my application need more pins on a PIC16F876 I'm thinking about
using
> the same four pins that send data signals to the LCD for sending the
signals
> to a 4x4 keypad.
>
>     Someone have used it? Any drawbacks? Any suggestions? The LCD data
lines
> wouldn't interfere with the keypad?

On my current project i use a daugherboard (manufactored by unknown company)
which has a 4x4 keyboard  and a 44780 compatible display on it. It uses the
same datalines for the display a keyboard using a HC373 to "select" on of
the two items. You need one extra line to handle the -OE and LE signal of
the 373.

This could be one idea to "multiplex" a display and keyboard uses latches of
bus-transceiver (i.e. HC245).

cu,
Christian

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