CFAH2004A-AGB-JP display problems


New member
I just recived my lcd from you guys and like a kid on christmas morning started wireing it up with visions of it shineing in all its glory....

to make a long story short here are the problems..
I wired it according to the diagram that has been posted here many tiems for the parallel lcd
the backlight works,
and the lcd test software says that the chip is working and is getting back signals on the busy flag line..
however no amount of contrast adjustment will allow any characters to show..
it is just like there is nothing being output to the lcd.. but the test software detects it and says that it is working...

any suggestions or should i ask for an RMA #??
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CF Tech

The LCDs are 100% tested at the factory, so it is not too likely that you have a bad one.

Contrast would be my first guess, but having the data lines crossed, open, or shorted could mess up the initialization.

Please check every connection very carefully and make sure that every pin on the printer port goes to the correct pin on the LCD and to no other.