serious CFAH2004A-TMI-JP problem

[stigmata]

Hello

I have a CFAH2004A-TMI-JP display (4x20 blue) and I can't make it work

All the wiring has been redone at least 20 times (i'm not joking!) and I'm 99% sure that all is ok on that side.

But still, no way to make it work.

When I boot the PC I don't see the "test-screen" with 1st and 3rd lines on and 2nd and 4th off, but everything is on except for the first 8 chars on line 1 & 2

Something like this (1 is ON and 0 is OFF):

00000000111111111111
00000000111111111111
11111111111111111111
11111111111111111111

[hope you guys can understand... im not good in ascii art]

well, after a few seconds this screen fades out, and never comes back until i reboot my pc.

what can I do???

thanks and excuse me for bad english!
bye!

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[CF Mark]

All the wiring has been redone at least 20 times (i'm not joking!) and I'm 99% sure that all is ok on that side.

It would have been good if you were joking.
If youve redone it 20 times, then obviously the previous times you did somthing wrong and have fried the LCD.

Bad luck, looks like youll need to buy another LCD, you wont get any warranty.

 

[stigmata]

if my lcd was fried it wouldn't even light up, isnt'it?

but it lights up every time i boot my pc, showing the strange thing i've shown in my first post... but only for a few seconds.

it also reacts when i run CFAH_WinTest, the white chars get a little brighter but there is no change for the dark zone

anyway, thanks for thinking that i was only here to get my lcd changed on warranty.

bye.

 

[CF Mark]

if my lcd was fried it wouldn't even light up, isnt'it?

The backlight really has no common components with the rest of a HD4480 LCD.
The backlight can work, and the display not, or the other way around.

Unless there is visual damage to the LCD (like burned tracks which can be repaired and sometimes will make the LCD to work again), there is nothing that can be done to fix it, hence me bringing up warranty.

 

[stigmata]

ok, got it... i fear theres nothing to do... but i will try again

well excuse me for complaining about your last post but i was very sad for seeing my new LCD dead on my desk, i'm sure you can understand me

bye!

 

[PaddyLong]

there is another post with 4 other people (myself included) with this same problem.

2 with the 20x4 white on blue
2 with the 20x4 yellow on black

I really think crystalfontz needs to look into this more if more people are having this same problem with similar units.

even if you don't replace the units or whatever (although that would probably be the preferred solution...) could you at least try to recreate the problem there and try to come up with a solution? surely the people who created teh circuit to begin with might have some idea as to what could be causing the problem? so please if you at least tried to come up with a solution rather than just saying "nope, those aren't ment for the computer so go away" it would make me that much happier and I might even think about ordering a new unit from you.

 

[stigmata]

You're right PaddyLong... I really disliked the answer, if I can't make the display work I think that sooner or later I'll buy another one, but not a CrystalFontz one. The problem for me is that I live in Italy and there's no choice to buy LCDs except CrystalFontz ones, and only the parallel version.

Hey Mr. CrystalFontz, why don't you allow we poor Italians to buy USB or serial devices? Why just parallel if we cannot use them on our PCs? Why not serial which is much more simple? OK, I think that shops here only want the parallel ones... you could suggest them to try with the other models too.
People here (my friends and all the guys on the forums and so on) would even buy directly from you, but the problem is shipment costs, it's too much expensive to buy directly from the USA...

(By the way, I think that if/when I'll decide to buy another display a character or graphic LCD from Holland will be my choice since being Holland in Europe will surely make shipment much more cheaper. They even make the wiring job for a little extra fee if you want.)


Now lets say something about my display.
Yesterday we tried our wiring on another CFAH2004A-TMI-JP display and everything went good. We tried another working wiring on my display and the problem remains.
The soldering on the PCB of my display has been done once (by a friend of mine who is expert in electronics and soldering) and all our famous 20 retries were only on the 5v - parallel wiring. The display has not been modified in any way after the very first soldering, and we are 100% sure that the problem is not there.
I'm quite sure that the problem is in the display itself.

 

[CF Tech]

The serials and USBs are both available worldwide. I am not sure why you think only the CFAH* series are available.

Shipping and customs can be siginficant on international purchases, we have found that FedEx is the only reliable way to make international shipments (we have tried UPS and USPS with quite sad results, DHL is good, but slightly more expensive than FedEx). Customs are dictated by your country we have no control over them.

As you have seen with your second display, if everything is done exactly right from the beginning it can work. I am very sorry that the first display got damaged. We test them all before they leave our factory so we know it would have worked if it was connected correctly the first time.

 

[Chris Stockton]

Hmm... I have tested out PaddyLong's LCD unit with my wiring. There is nothing wrong with the Circuit, there is no way this could have been tested in the shop because I was there when the first soldering was done to his unit and nothing was screwed up. The LCD comes on with the TEST screen and nothing else. Could it be that this unit requires a different Curcuit design then the ones posted. Because it seems like there is just no data (Or Wrong DATA) getting to the unit.

But there is no way this unit was tested with the current wiring setup we have on it. Not unless when you test, you only look to see that the unit turns on.

Also the fact that you do not support these units if they are used with a computer. (Off-color language removed. -admin)
*********EDIT************
I Just finished reviewing your Policy lists and in there nowhere did I see that you do not support units that are to be used with Computers. All it stated is that they should not be used with Life Support devices.

 

[CF Tech]

The units are tested on a mass-production testing machine as part of our quality program. For reference the factory is ISO-9001 certified.

These are electronic components. If they are used within the parameters specified in the data sheet they, we guarantee them to meet specifications stated in the data sheet.

These modules have sensitive electronic circuits on them, which are susceptible to damage--especially in a prototype environment where connections are being "tried" (such as when a one-off cable is being made, as opposed to plugging it into a known good circuit), and also when proper ESD precautions may not be in practiced.

These modules are not intended to be used by hobbyists. Some hobbyists use them with great success, others will have trouble.

Since we have seen a great amount of trouble when hobbyists attempt to connect the modules to a PC's parallel port, we have decided to continue to sell the module at small quantities, but to warn our customers that certain applications (specifically connection to a PC's parallel port) will not be supported, and we will not accept returns for modules used in this type of application.

I suspect that this module somehow got damaged in one of the many attempts that were made to connect it. I do not suspect that it arrived in a non-working condition.

By the way, the "test" screen that is many times offered up as "proof" that the wiring is done correctly will show if only Ground, Vcc and Vo are connected to reasonable values (typically 0v, 5v and 1v). Leaving the data & control lines disconnected or connecting them in any random fashion does not guarantee that the "test" screen will or will not be displayed.