> This was using sample code I found on the net and not code I
> wrote myself so I can't see how code can be the problem

Don't count it out. More than once I've found code that purports
to do something but find it just doesn't and never will

> issue with this specific pic chip

That's a problem with downloaded code. It may have worked for
the author in a particular situation but isn't robust enough to work
anywhere else

> the 18LF45k22 chip is running off a 3V supply and the display
> is running off 5.0V supply

Can you try a 5V PIC to rule that in/out ? Or raise PIC Vcc
and lower LCD Vcc to get them closer ?

Every 8th line sounds like it might be a paging issue if your display
has 8-pixel high pages. Might there be some portion of the code
which clears the page just before the 8th line is drawn ?

Joe
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