I had the same problem with one of my projects some time ago. The circuit was working fine with one type of LCD but wouldn't with another type. When trying to locate the fault I discovered it started working when I would touch the busy flag pin (DB7) with either a CRO lead or my finger. I think I put in a pull-up or pull-down resistor and it worked, but as I was going to use the original LCD in the end this was removed. I was using the 4-bit interface. I haven't had time to go back and have another look at it. Keep us posted to any developments. Gary. -------------------------------------------- Email: Gary.Fowler@dsto.defence.gov.au Phone: +61 8 8259 5767 Fax: +61 8 8259 5672 Defence Science & Technology Organisation PO Box 1500, Salisbury, South Australia 5108 -------------------------------------------- Date: Tue, 16 Sep 1997 11:29:49 -0700 From: Ed VanderPloeg Subject: [OT] LCD "busy" signal I'm trying to use a PIC to drive a standard, run-of-the-mill, LCD display, and am having trouble understanding the operation of the "busy flag". For efficiency I'm trying to wait for the busy signal as described in the databook but it's not working as expected. Seems like the LCD is forever busy.