634 Serial -> very weird behaviour

El Ente

New member

I own a 634 Cryztalfontz LCD display since summer 2004 (v2, I think) and now I'm getting weird issues out of nothing. (by the way, it's not :this one, it's a new one :D)

It worked without a single problem until now. Suddenly, it started to show weird characters, then no characters at all, turning backlight on and off.. and finally powering itself off and on randomly.

If I format my PC or restore from a Norton Ghost Image, I'm able to make it work again... but it lasts only 10-20 minutes until it starts doing weird things again.

Also, I found that switching from different baud rates may make it work for some minutes.

For example... if it's acting weird, I power off the PC, change the back switches on the LCD from 19200 to 9800, power on again, configure CC1 (or CC2, it makes no difference), and it works for another 10-20 minutes... then it goes crazy again.

Both solutions are not 100% effective, I mean, sometimes work (formatting, changing baud rate) and sometimes not :confused:

I made no hardware changes on my PC recently, nor software ones, so that's why I said this behaviour is out of nothing... I don't know what to do and this working-for-10-minutes thing is just frustrating :mad:

Wintest shows the same as CC1 and CC2... I close everything, start wintest, but that crazy behaviour is still there.

One thing that surprises me is that even with this crazy behaviour, it seems to follow the on/off instructions sent by CC or wintest... I mean... it's acting like crazy but if I turn off the app, it always follow the instruction-

Any help would be much appreciated
thanks for your time and I hope you can help me :rolleyes
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Last edited:

CF Tech

OK. This certainly seems odd.

I think the first thing would be to get the display and a copy of WinTest to another machine, so you can see if the problem is only on your PC or if it follows the display.

Have you tried the other serial port?

El Ente

New member
Thanks for your reply CF Tech:

I just came from a friend's house. I plugged the LCD and it shows exactly the same behaviour as in my PC.
In 10-20 minutes it works PERFECT: boot screen, CC1, Wintest, etc... everything's OK.

After some minutes running CC or Wintest, it starts going crazy: blinking, no characters, etc etc...

I can't try another serial port as neither my PC nor my friend's hace a second COM (damm mobo manufacturers :p)

Any clue?

My specs:
Msi k8n Neo Platinum
amd A64 3000+
1 Gig Ram
3 Hard disks (2 IDE & 1 Sata)
Asus DVD Recorder

My friend's Specs:
Soltek Mobo
Athlon XP 2500+
512 RAM

Both running WinXP SP2 updated with hotfixes@ windows update

CF Tech

Something must have gone South. Please write support{at}crystalfontz{dot}com (edit to '@' & '.') with your invoice number and we will see what we can do.
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