HD44780 LCD Display Trouble (please help)

totalconfusion5 · 11-01-2005, 04:26 PM

I recently recived a hd44780 4x20 and wired it up to what i thought was the correct pins on the parallel port.
Result: The two test lines

So then i consulted the diagram to find that i read it wrong. i corrected the wiring.
Result: The LCD displays 3/4 full with white squares 1/4 is just blank. After a min that faded away. Then Nothing

I removed all the wires to the parallel port leaving just pins 1,2,3,5 and 15,16 hooked up to the apropriate power,.... Ground and +5v.
No test lines display.

Have I ruined my lcd?

i will be forever thankfull to whoever can help me

I already extensivly searched google and fopund nothing.

-Dylan

totalconfusion5 · 11-01-2005, 05:28 PM

I also used the program "portmon" to monitor the LTP port.... and it doesnt read anything when i run LCD smartie, but when i run lcd smartie for serial portmon goes crazy ... could it be the software?

Also arent the 2 test lines... 1 and 3 .... supose to always come on when u give the unit power?

Wiredwrx · 11-01-2005, 06:08 PM

Quote: Originally Posted by totalconfusion5

I also used the program "portmon" to monitor the LTP port.... and it doesnt read anything when i run LCD smartie, but when i run lcd smartie for serial portmon goes crazy ... could it be the software?

Also arent the 2 test lines... 1 and 3 .... supose to always come on when u give the unit power?

That is the problem with LCDs, they have a million wires, and have limited usefullness.

First, confirm that you have everything correctly wired.

Did you short anything. Perhaps you reveresed power and ground, which would bork the unit, or make it work in wierd ways, depending on what got fried.

Nest, it could be the sw, or your LPT port. Is it enabled in your BIOS. Does a printer work. Is your printer port setting correct, like EPP, ECP, ECP/EPP. I do not recall which setting is correct.

Did you somehow feed power into the LPT port accidentaly. Of course, that could cause some problems also.

THat should get you started.

Michael

CdRsKuLL · 11-01-2005, 06:13 PM

when using lcd smartie I had to install a nport something file, which you can grab in there faq section if I remember rightly, on my 2x16 on power up even when its not connected to the lpt port the screen lights up with 2 solid bands across

CdR

totalconfusion5 · 11-01-2005, 06:52 PM

I hate to admit it but i think its fried .....ugh well now i have a cool 20$ blue light right? lol

i still think its wierd that portmon doesnt show any LPT activity ...i had it set to EPP wich i belive is recomended and nothing

..... new lcd time.... i hate waiting for things in the mail

Thanks anyway

AngryMan · 01-23-2006, 09:50 PM

Quote: Originally Posted by totalconfusion5

I hate to admit it but i think its fried .....ugh well now i have a cool 20$ blue light right? lol

i still think its wierd that portmon doesnt show any LPT activity ...i had it set to EPP wich i belive is recomended and nothing

..... new lcd time.... i hate waiting for things in the mail

Thanks anyway

IM having trouble with my lcd too.
what programs did you test it with besides lcd smartie?

I can get it to work "okay" with lcdcenter, but everything else I try to use it with doesnt work right.. if I use it with smartie I get all kinds of artifacts, and the occasional unhandled exception. and god forbit I should accidentally click the "backlight off" button..
anyway, im using a:
16x2 lcd with
hitachi hd44780 "proccessor" connected via
parallel cable. LPT1, port 378 - ECP
and windows xp sp2...

djchicago · 01-24-2006, 12:18 AM

try this link

http://www.cwlinux.com/eng/products/products_cw1602.php

AngryMan · 01-24-2006, 08:06 PM

Quote: Originally Posted by djchicago

try this link

http://www.cwlinux.com/eng/products/products_cw1602.php

this doesnt help us much with the hd44780 lcd. and since programs like centrafuse dont use WinAmp to play, this is effectively useless.

come on people, we need help with the Hitachi HD44780 PARALLEL interfaced LCD panel.

someone must have some input here..