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Problems with a HD44780 4x40 display


New member
Alright, I have a CF633 going in another computer, so I have at least some idea of how to get it going. When it comes to making my own screens however I am having difficulty. The issue here is that I have no display output.

Backstory: I currently use LCDStudio to run the 4x40 display based on an HD44780 (or pair for those that care). Thier implemetation has had problems since I upgraded to a dual core, and have ceased support, moving to software that runs graphic displays. The wiring they use is identical to that which is described on the CrystalControl wiring diagram. So in short, LCDStudio works, the problem is not hardware, but I need a different program because it has "issues".

I took CPU Usage Bargraph.2004, renamed it to .4004, and changed the text on the inside of the file to:

I have had difficulty finding a screen that is for a 4x40, to remove that as a problem, and I don't know whether it's the configuration of the display or the screen file.

I do not see any activity on the display, crystalcontrol should be initializing the display at some point (so it should blank) and I do not see this behavior. I can also open LCDStudio at the same time and LCDStudio operates like nothing is different.

What can I do now, I don't know if crystalcontrol is running the display, and I don't know if my screen file is faulty and it's just not telling me the problem. If i can get something on the display then i can bang my forehead bloody while tweaking and copy-pasting till it ends up with what I want, I see we have a new syntax document now, which is much better than last year when I was getting the CF633 going.

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CF Mark

There are parallel port driver problems with CrystalControl2 :(
Im working on finding a replacement for the driver currently being used.
No ETA on a fix.


New member
Sorry to have bugged you, the release notes lead me to believe it was finally working :(...at least the CF633 works then.

When you say the driver, are we talking the interface to windows from CC2, or a driver that would be installed so that we then can use the port : problem exists inside or outside CC2?

CF Mark

I switched over to using the old driver installer which i thought would fix the problem, but it didnt :(
So it appears the driver itself is at fault.

Its the driver which allows CC2 direct access to the parallel port.
Any new driver we use will need to be supported internally in CC2, so there cant be any temporary fix.
I have been looking at alternatives, but no suitable replacement has been found yet.