Newbie with Question

[JWilson]

I have the Tech Arts AD9S12DP256SEP developement board. I am trying to program an LCD screen (http://www.allelectronics.com/spec/LCD-87.pdf).

I know that I have to initialize the LCD before I can do anything but I am really new to this and thought someone on here could point me in a good direction. I am not expecting anyone to just give me code on how to do this, as I want to learn. What I am asking is for someone to give me a link or something to a good document to read and learn the very basics of how to do this.

Thanks in advance and sorry this question is so elementary.

Edit: I am going to use C to program this in.

John

Message Edited by JWilson on 2006-09-2910:06 AM

[mjbcswitzerland]

Hi John

Try the following:
1. http://212.254.22.36:8080   this is a web cam to an online LCD

2. Connect another browser window to http://212.254.22.36:8081/0     Here you can control the display - write messages to it, control its contrast and back light intensite.

3. On the web page controlling the display (which is infact running on a M9S12NE64 which is directly controlling the LCD via a 4-bit bus and its contrast and intensity with PWM outputs) there is a link to a program called "VIPpanel". If you install this you will also have some quite detailed documentation installed alongside with information about controlling the LCD (although not at the bit level). However this program is an LCD simulator which runs on your PC and has built in LCD controls to allow you to test all LCD commands, including creating new characters and viewing the inbuilt character set. Now this won't tell you exactly how to write C code for it but it will allow you to learn all about what can be done with it. It also has some animation support which is quite fun.
As explained in the documents (if any are missing check out the "VIPpanel front panel simulator" at http://www.mjbc.ch/index.html.en) you can also set up the simulator to connect via the Internet to the LCD viewed by Web cam and you can then control this rather than a simulated one on your PC screen - it allows testing of all commands on a real display - you don't need one locally.

4. If you want to program the LCD on a HC(S)12 you can get all necessary code (including a built in LCD simulator in the development environment) from the uTasker project. Get all details at www.uTasker.com - it is free for non-commercial use and has a growing user community so will enable you to get up to speed very fast. There is a simple application form there and you will receive all project code (apply for the NE64 project so you get the correct hardware support for the HC(S)12) and the uTasker simulator, enabling you to write and test your code without hardware - after cross-compiling to the target the code will also run there...

Good luck.

Regards

Mark Butcher

www.mjbc.ch / www.uTasker.com

Message Edited by mjbcswitzerland on 2006-09-2903:14 PM

[bigmac]

Hello John,

For LCD displays based on the HD44780, have a look at AN1774 where initialisation is detailed, for both 8-bit and 4-bit parallel interface modes.

AN2940 may also be of some use.  It is primarily intended for HC08/HCS08, but since C code is used you may be able to easily adapt to HCS12 use.

Regards,

Mac

[J2MEJediMaster]

Check out this forum thread here. It provides a discussion of LCD programming and points to some useful application notes. It's 8-bit stuff, but should still be useful.

---Tom