Help with cfah1602b-yyb-jp


New member
Ok well I think I have this one wired up correct, when I apply power to the unit, I get a single row of dark boxes accross the screen.

But when I try to use any of the lcd controller software, lcdsmarti, lcd center2.0, crystalfontz own software, nothing works with it.

Could it be that in most of the scamitics there is ground connected accross db25 pins 25-18? I left this out as the instructions I received with the lcd did not mention this.

Please any help here would be great.
email if possible at

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CF Mark

The black boxes mean you have got the power and contrast set up ok.

The problem with software not being able to use it is probably because you have wired some of the control or data lines up wrong.
See if you can gte someone else to check over your wiring.


New member
thanks for the reply, figured it out around 3am, out of the 30 or so connectors I have here, it figures the one I used had a internal short in it.

Now it works but the backlight is really dim, almost not on. I have it getting power thru pins 15 and 16, with a switch and a 100ohm resister inlin with it.

thats my next project.


New member
100 ohm resistor in-line with the backlight? no wonder it's really dim.. Use about 6 ohms in-line with a 100 ohm pot.......... The pot is optional but the resistor should NOT be that high...