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Hi all,
I own Nan Ya LMCEAS184C1 240x128 graphical lcd and I´d like to connect it to paraller port. I wired it as follows:

pin
1 VSS -> 0 V
2 VDD -> 5 V
3 N.C.
4 C/D -> LPT pin 17
5 RD -> LPT pin 14
6 WR -> LPT pin 16
7 DB0 -> LPT pin 2
8 DB1 -> LPT pin 3
9 DB2 -> LPT pin 4
10 DB3 -> LPT pin5
11 DB4 -> LPT pin 6
12 DB5 -> LPT pin 7
13 DB6 -> LPT pin 8
14 DB7 -> LPT pin 9
15 CE -> LPT pin 1
16 RST -> "autoreset" explained later
17 N.C.
18 MD2 -> 0 V
19 FS1 -> 5 V
20 FG -> 0 V

I made reset at startup by connecting reset pin 16 with 100 nF ceramic capasitor to GND and with 10k resistor to 5 V. It works OK.

I think display is working because when I turn contrast trimmer it gets lighter or darker. But I haven´t got it work with computer. I have tested different test programs and LCDinfo but no success. I have also tested linux console driver with Debian (kernel 2.4) with no success. It tells that it have found T6963 (when I load mdacon module) but when I change to tty13 computer hangs. Also LCDproc and LCD4Linux don´t work.

Can controller be defective? Is there any reliable test method? I don´t own scope at the moment.

If you want to see datasheet, it is available in my Yahoo Briefcase:
briefcase.yahoo.com

ID: reallcdman
passwd: t6963c

I have had several of this exact lcd myself so I can confirm it works with LCDInfo. Ok, that doesn't help you much.

I tried to look from my archives but wasn't able to find any schematics for this display so I don't think I ever made one. But your connection already looks fine to me.

I suppose you have checked that the program settings match your wiring ?

Defective controller is always a possibility but I don't think that happens very often. Was this new or used display ?

Sounds like the contrast circuit in the display is also working fine as you can adjust contrast but for some reason the communication between the T6963C chip and PC is not working.

To test the controller it would be possible to write some code that first writes data to the lcd memory and then reads it back and checks if it was the same. But I don't think this would work now as the interface between the T6963C and PC doesn't seem to be working.

Lcd is used one. Logic power is produced by 7805 regulator and few filter capasitor, one 100 nF ceramic connected directly beetween lcd pins.
Cable is made from old printer cable and it is about 160cm. Is it too long? My bios settings for lpt is EPP+ECP, is this right? My computer is 700 MHz Duron with Win2000. Motherboard is Abit KT7 Raid. I have tested it also with old P200, no success again.

I have used cables longer than that with success but you can never know. Sometimes 100 cm might be too much. EPP+ECP has worked fine for me but you could try different settings.

It works now! I shortened cable from 160 cm to 10 cm and soldered things again. So problem was either too long cable or bad solderings. Thanks for help.