A non-purist but effective solution would be to use the
calculator electronics intact and access its keyboard
functions from the PIC.

-----Original Message-----
From: Thomas M. Alldread <tmaldred@MAIL.ISLAND.NET>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Wednesday, 11 February 1998 09:06
Subject: ?Utilization of Calculator LCD displays?


>Greetings:
>
>        I wish to utilize the display in a low cost
calculator for a
>micro-controller project to provide output to the user. The
cost of a
>calculator can be much less than the cost of a new LCD
display module with
>similar size characters. If I can successfully adapt the
display then I may
>look into the possibility of also utilizing the calculator
keyboard to
>complete the user-machine interface.
>
>        I purchased an inexpensive (about $5) solar/battery
dual power desktop
>calculator for exploring the possibilities of using the
bold 0.5 inch 8
>character display as the readout for my project. The
characters are in the
>solid bar 7 segment format as opposed to the dot matrix
type. I am hoping
>that I will be able to interface the micro controller to
the display via a
>standard multi-character 7 segment LCD driver chip.
>
>        I wonder if someone in this list that has made past
attempts at adapting
>similar displays for micro controller projects or has
general knowledge
>about typical calculator LCD displays?
>................