LCD proposal cont'd

So, to implement this LCD Project on Mac OS X, I figured I would have to write a daemon or command line utility that would accept messages to display. Then write a bunch of scripts or clients to display server data, then have users make their own if they wanted. (Sort of like LCDproc.) Obviously this would be a pain, and have little usefulness for existing applications.

Then I discovered an application that is designed to take message notifications from applications and display them to a user. Growl will allow me to just code up a small "Display" plug-in and immediately, the LCD will be able to display noitifications from a whole list of supported applications.

This might turn out very useful and functional!

LCD Project Proposal...

So I have this idea for a LCD controller project for my Mac.

1. Take a USB -> IEEE 1284 parallel printer adapter, open it up and take off the centroncs connector.
2. Connect it to a parallel character LCD which uses the Hitachi HD44780 controller.
3. Write a program on the Mac to send data through usb to the LCD.

Why is this any different from all of the other LCD's I have seen?

Well, any LCDs designed for the Mac use a serial connection. May others use serial connections too. This would require a USB -> RS232 adapter . This doesn't seem very elegant considering the project this will be a part of (more to come...). Any that use USB are generally pretty expensive:

http://www.j-works.com/jsb815.html - $65 for just the controller!

http://www.usblcd.de/products/showprod.php4?gr=1&lang=en - 45 euro for the controller.

I imagine I should be able to make this for $10-$20.

potential problems:

• The IEEE 1284 USB adapters are made for printing, and maybe this won't work with an lcd (I'm not sure this will be a problem).
• writing to USB devices is a little less obvious to program than writing to serial devices using the darwin IOKit. I sould be able to work this out though. You just can't open up a terminal program and make it work though.
• Parallel won't let me use a keypad on the device like a serial controller would. But hey, I can use usb, right?