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Removing the potentiometer? just cut it out and have the 3 wires which were connected to it hang around, connected to nothing?
I'm not very good in this electronic stuff yet - sorry

Just found out that some of the voltages change when the lcd is in use for some minutes - gotta go now, lord of the rings premiere
thx so far - cya 2morrow

Yep, just cut out or desolder the pot and then measure what one of the wires (pin18) gives.

Just a thought, how do you have the potentiometer connected, eg. which wire goes to where ?


No problem, you can practice now.

I recomend to check all connections(solders etc.)again. Mine has worked fine after I changed my LPT cable.

I cut the poti out - now i got 0.00V at pin18 :/? does this mean my display is trash? or have i got a version w/o built-in inverter for negative voltage?

Hmm, strange.

I only see one CFAG12864B-TMI version at the Crystalfontz site and it's the CFAG12864B-TMI-V. I guess that -V in means negative voltage circuit and the models without it have -N. Any chance they might have a model without negative voltage generator ?

You could try unsoldering all wires and then only connect +5v and GND and measure the pin18 again hoping it would work this time.

If none of this works then you could try with external negative voltage circuit. Some circuits for this are in the hardware part of this forum: http://www.skippari.net/phpBB2/viewtopic.php?t=63

So just have Pin1 and 2 connected?

Oh - and pin14

With only pin 1, 2 and 14 connected its still 0.00V - begins at about -0.2V and drops to 0.0V within some seconds

Yep, pins 1 and 2 only. Shouldn't be need for pin 14 when just testing voltages.

EDIT:
You were faster than me

So still nothing. I don't know, either the negative voltage circuit is broken, doesn't exist, or there's something that I just don't get right now.

hmm
well, so something with the display seems to be wrong
but i still dont understand why there were those white lines - doesnt this mean that there was enough voltage?

I've noticed that sometimes when pluggin in or removing display from parallel port there are some lines on the LCD although no power is connected.

Thata is due to stactic electricity , i also notice those sometimes with my display when i disconetct it or has i touch some of the paralel pins.

AS for the cristalfontz display , thata's very strange !!
Probably the display is malfunctinoing , you should try to get a new one to see if it was the display was the guilty

SAmtech

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it is too bad about the display. i only have bad news for warth, crystalfontz will not take it back if it has been out of the plastic bag! trust me i have already tried .

well that program that you sent me henri produced readable text!!!! i got this by having my parallel in normal mode. as of now i have it in EPP(EPP v1.7) and i can't get anything. i will try all of the parallel modes and get some pictures to henri. THIS LOOKS AS IF IT COULD WORK. i still need to build that reset circuit though.

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...and the geeks shall inherit the earth (Bob 5:5)

Well ,that's realy very bad to hear about Cristalfontz , isn't there a waranty on the Display , so for example if i ordered one for portugal and if i got the badluck of it to be malfunctionning from the beguining due to a defect i would be trouhing money in the garbage can

As for you , congratulations on your progress , reading something on it at least it's a good sign

AS for the reset circuit i'll aso include it on my schematic

Samtech

_________________
The Power is Within your Hands ,use it wisely...

XP 2000+
A7N8X Dlx
256 Mb DDR PC3200 OCZ
GF 4 Ti 4200 128 DDR
180 Gb
Studio PCTV Pro