Contrast on LK204-25PC

Rikk · Post by **Rikk** » Sat Mar 02, 2002 3:03 am

I have an LK204-25PC, bought it about a week ago all up and working apart from one thing thats begining to annoy me.

The first time I used the display the contrast was fine, second day I turn in the system and the display was blank. AFter lots of messing around I found if I unplug the serial lead and power it up, then use lcdsmartie it works fine.
But as soon as the machine is restarted I'm back to no display. I've downloaded contrast and the alpha demo from MO. Once the display has powered up, none of these will change the contrast at all. If I unplug the serial power back up then plug it in I can get control back.
LCDsmartie always reports the contrast as 16.
Can anyone help at all, this is really beggining to get to me.

Thanks in advance.

............Rikk

Post by **Cheese** » Sat Mar 02, 2002 8:09 am

Hi mate... not 100% sure what's going on here so let's try a few things...

Reset the display and kill all lcd app (smartie included) - now you're telling me that after selecting a port, com speed and clicking on the initialise button that the contrast program doesn't seem to function? You can't the test message (after clicking on the test button) and putting the contrast up high (somewhere like 150)?

If that works ok then I think your problem might just be lcd smartie setting the contrast wrongly every time it starts... do you have any problems if you set and remember the control using mo's contrast program and then use lcd center? (lcd center doesn't touch the contrast setting so is a good test)?

Cheers,

r.

<font size=-1>[ This Message was edited by: TheCheeseMan on 2002-03-02 08:11 ]</font>

Rikk · Post by **Rikk** » Sun Mar 03, 2002 3:56 pm

Hmm, this is strange..well to me

From power on wether just machine or pulling the power on the display I get :-
Contrast - no responce at all
Matrixdemo - no response at all
LCDsmartie - no response at all

Now if I leave it plugged in and pop the serial cable out then back in I get, all the software starts working, although matrixdemo and lcdsmartie reads the contrast from the display as 16.
LCDsmartie works fine at this point, although matrixdemo needs the contrast wound up from the 16 it finds to something higher.

Open to any suggestions

Rikk · Post by **Rikk** » Tue Mar 05, 2002 9:56 am

Anyone lend a hand????

Pretty please.

Post by **Henry** » Tue Mar 05, 2002 10:06 am

contrast 16 is waaaaaaaaaaaaaay to low... the display needs to be at 120+/- be it in Smartie or in Alpha Demo...

Try to turn the backlight on and off, see if that works.

Rikk · Post by **Rikk** » Sat Mar 16, 2002 2:48 am

Sorry I've not got back I've been rather busy

It boils down to this, when I power my machine on the backlight comes on and thats it, it's completely unresponsive to ANYTHING, untill I unplug the serial cable (at which point the welcome message appears) then plug it back in. From this point onwards ALL software works with it fine.

Any clues??

Post by **Aniso** » Sat Mar 16, 2002 12:57 pm

I am going to guess that you have a laptop? If not that, then please tell us about your PC.

Rikk · Post by **Rikk** » Sat Mar 16, 2002 2:03 pm

Motherboard - Tyan Tiger mp
cpu - dual Athlon MP1800
ram - 512mb in 2x256mb ddr
os - windows xp pro
no other devices on serial ports.

Can't think of anything else that may be relevant

Post by **Aniso** » Sun Mar 17, 2002 12:51 pm

Well, Not really. I don't recognise the motherboard, but that's no reason to mock it. I have seen this kind of problem about 10 times in the last several years and it has always been Laptops. I am fairly sure it is the serial port hardware, but I don't know the details.

Do you have any other way to test theories? Another PC? A serial card? USB to serial converter?

Rikk · Post by **Rikk** » Sun Mar 17, 2002 1:55 pm

I have several pc's here I'll rig it up to one of them and give it a try.

Out of interest if it works on the other machine is the only solution going to be a diferent motherboard??

Rikk · Post by **Rikk** » Fri Mar 29, 2002 9:27 am

Sorry for the delay.

Tried it on a Compaq I have here running as a webserver and it does the same on that.

Totaly unresponsive till i pop the serial cable out then plug it back in, the last displayed text is still on screen so it appears to be an issue with contrast. But ntill that cable is pulled out and pushed back nothing will change the contrast on it.