Hi all,

Thanks Mel for looking. LCD is on PORTD.4 - PORTD.7 (MSSP turned OFF) RS/EN on PORTC 4, 5. So no sources of interrupt from there. Also as Darrel mentioned that LCD is a synchronous interface it should not matter much.

If I am using some of your routines or macro or I2 (I.square a.k.a Instant Interrupt) and find that it is using the PBP macro for checking page or resetting to page zero then I use that. If I am using my own ISR I use banksel. Is this wrong ??

Darrel I have never bothered how the data is actually transported to the LCD. I am studying now. Can there be issues if the timing between two nibbles get spoiled for the program doing too much in Interrupt.

I am re-structuring the code and would post it here. Also I would use LCDs from different brands and see if this cheap Chinese LCD (In fact all that are available are Chinese) is a culprit.

BTW I noticed that PBP sets the PINs as output every time LCDOUT is used. Was my observation correct. Can this be safely removed as I have manually set it as output and never use the LCDIN command in my prog.