Hi All,

My project is using a hitachi compatible character lcd module in 4 bit mode,
and using the xlcd library from the mc18 libs.

Problem is that quite often, the LCD "goes wrong". After a few seconds of
use, at random, the LCD will start misbehaving - somtimes the screen blanks,
often it displays random characters.

To get it working again, I have to reset my circuit.

I'm only a hobbyist and i'm struggling to work out what the cause is.

The wires between my circuit board and the LCD are short - not more than 3".
I've tried adding a decoupling cap at the power pins of the LCD module.
I've tried a different LCD module, to no avail,
The circuit (pic and lcd) are powered from a 7805 1amp.
My PIC is an 18f252 clocked at 20 MHz with a crystal.
I've tried massively increasing the time delays that the xlcd routines ask
for:-
   the DelayFor18TCY routine delays for 100 cycles
   the DelayPORXLCD routine delays for 70 ms (350,000 cycles) instead of the
required minimum of 30ms
   the DelayXLCD routine is delaying for 14 ms

Nothing i've tried has helped. I'm not sure whether its a software or
electrical problem.

Has anyone got any insight or pointers for how i might diagnose what's going
on?

Thanks

slip
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