Hi, PicListers,

I am in the process of adding a LCD display and a keypad to
a robot rover I am developing in my free time. When having to
decide how to interface both of them to my master PIC (a 16F877)
a had little doubt with the LCD display (that is, directly
to the existing ports, since only 4+3 pins are needed) but it
was not so clear for the keypad : it needs 13 pins if I interface
it directly to the PIC.

The question (a philosofical question) is :
is it worth to add a decoder between the keypad and the PIC so as
to save I/O pins (using 4 instead of 13) ? Or it makes more sense to
do with PICs whatever can be done with a PIC, adding -if needed-
more PICs and forgetting the rest of logic ICs ?

What do you think about it ? Has software killed hardware ?
Perhaps killed is not the most approppriate word since software
needs hardware, but I think that you realize what I mean ...

--------------------------------------------------------------
     Joan Ilari                 e-mail : joan@ilari.org
     Barcelona                   www   : www.ilari.org
     Spain                      Voice  : +34 93 431 96 39

"I've seen things you people wouldn't believe. Attack ships on
 fire off the shoulder of Orion. I watched C-beams glitter in
 the dark near the Tannhauser gate. All those moments will be
 lost in time, like tears in rain. Time to die..."
                                               -Blade Runner-
---------------------------------------------------------------

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