programming the HD44780

**666** · 06-28-2004, 12:37 PM

anybody ever program anything for this? i've googled it and got a lot of results and got some source code... but too lazy to actually de code the code

i'm going to program it in perl and i installed Device::ParallelPort already but i'm stuck. how do the bytes/addresses and stuff? any help would be nice.

thanks

**Superduck** · 06-28-2004, 01:25 PM

Just out of curiosity, how complex are you looking at making this? What are you useing the LCD for? There's enough software out there already that you can do almost anything you want.
The easiest way to get custom stuff written on the screen would be to use LCDPrint and use batch files or something.
I'm just using Crystal Control at the moment. Though I'm not doing anything really specific right now.

This link has a good example in C, along with some fairly good documentation as to what things do. It's also got some links to other sites. If you want to google some more, I found that "parallel hd44780 control", or something like it, would return the best results.

Anyway, good luck,

Kris

**dug1967** · 06-28-2004, 01:46 PM

Hey SuperDuck, do you have any knowledge or experience on graphical LCD displays? Like the GLK12232-25-SM from Matrix Orbital?

I just finished hooking that up to my CarPC and am having little luck in locating a decent software package to do basically what you said above;

"The easiest way to get custom stuff written on the screen would be to use LCDPrint and use batch files or something."

All I want the screen to do is run through some canned text and graphics.... doesn't need to show any useful information...other than maybe the time would be cool.

**Superduck** · 06-28-2004, 02:00 PM

Originally Posted by dug1967

Hey SuperDuck, do you have any knowledge or experience on graphical LCD displays? Like the GLK12232-25-SM from Matrix Orbital?

I just finished hooking that up to my CarPC and am having little luck in locating a decent software package to do basically what you said above;

"The easiest way to get custom stuff written on the screen would be to use LCDPrint and use batch files or something."

All I want the screen to do is run through some canned text and graphics.... doesn't need to show any useful information...other than maybe the time would be cool.

Unfortunately, I haven't worked with a graphics LCD yet. Funny you should ask. I've got one coming in the mail. I still haven't really looked into controls for it yet. I'll wait til I get it, as I don't know anything about it yet.

Let me know if you find anything,

Kris

**dug1967** · 06-28-2004, 05:45 PM

I will most certainly let you know if I find anything.... so far what I have seen has not been to helpful. There is one called LCDC, which is supposed to be so good that you have to pay for it ($20)..... will I am glad it has a 30 day trial period.... cause I can't even get it to do a damn thing.

Which graphics screen did you go with?

**666** · 06-29-2004, 12:24 AM

i am trying to write a plug-in for GAIM (http://gaim.sf.net) and whenever i get a message it'll show up on the screen. my screen is only 24x2 though. i'm probably gonna make it so that the name is on the first line and the message is on the 2nd scrolling.

thanks for the link, i will look at it later.

:-D

**dignome** · 06-29-2004, 12:49 AM

If your doing this in Linux, there is something called LCDProc. It is quite easy to develop for, as it it has it's own widget set for lcds and uses sockets for communication.

http://lcdproc.omnipotent.net/?continue=yes

**666** · 06-29-2004, 01:23 AM

uhh windows

but i think i got it i was reading http://www.seiko-usa-ecd.com/lcd/pro...structions.pdf

i think you just set the RS and the R/W bits and then just send hex bytes to somewhere... i will see if other people's source codes agree with that

**Rob Withey** · 06-29-2004, 02:33 AM

Originally Posted by 666

i think you just set the RS and the R/W bits and then just send hex bytes to somewhere... i will see if other people's source codes agree with that

Other way around. Set the hex bytes and RS, and then strobe the R/W bit to latch the data.

Some source for a 44780 lcd/vfd interface is in my player source on my site. It uses a 4 bit interface to keep the wire count down, so it's not compatible with most of the wiring diagrams you see around the web.