possible help using a vacuum flourescent display?

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rebeltaz
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possible help using a vacuum flourescent display?

Post by rebeltaz » Mon Sep 07, 2009 7:24 pm

I have a now obsolete vacuum fluorescent display manufactured by IEE. I contacted the company and they were kind enough to send me a datasheet for the device. Unfortunately, I can't seem to get it working right. This particular display was custom designed for a customer as a serial device.

I have tried various baud rates and settings, since the settings shown in the datasheet didn't seem to work right, and all I can get to display is gibberish. I am trying to use terminal programs under Windows XP, such as RealTerm and TeraTerm Pro, since I want to use it to display information generated on the computer.

Can someone take a look at this datasheet and see if you can help me figure this out? Thanks....

You can download the datasheet from:
http://www.RobotsAndComputers.com/temp/ ... 2_REVA.pdf

---
Derek Tombrello
http://www.RobotsAndComputers.com
Derek Tombrello
http://www.ShelbyCycle.com

http://www.RobotsAndComputers.com

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MrAl
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Re: possible help using a vacuum flourescent displ

Post by MrAl » Wed Sep 09, 2009 7:10 am

Hi,

A quick idea (i did not study the data sheet very well yet) would be to try the self test first.
Did you try that test first, and if so, what were the results?
LEDs vs Bulbs, LEDs are winning.

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rebeltaz
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Re: possible help using a vacuum flourescent displ

Post by rebeltaz » Wed Sep 09, 2009 7:50 am

MrAl wrote:Hi,

A quick idea (i did not study the data sheet very well yet) would be to try the self test first.
Did you try that test first, and if so, what were the results?
Yeah... I did attempt to try the self-test mode, but since this is a custom designed display, I think they reused part of the original datasheet without reading it completely. It says to ground pin 25 of J1 before and while powering up. Problem is that J1 doesn't have 25 pins. On this custom design, J1 is only a 4 pin connector. Without a complete schematic of the board, I have no way of knowing what or where T0 is.

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Derek Tombrello
http://www.RobotsAndComputers.com
Derek Tombrello
http://www.ShelbyCycle.com

http://www.RobotsAndComputers.com

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MrAl
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Re: possible help using a vacuum flourescent displ

Post by MrAl » Wed Sep 09, 2009 10:49 pm

Hello again,


Oh geeze, i thought you already had a data sheet that was for the exact part you have
and just couldnt get it to work. If the data sheet is for a modified part it is going to
really be pot luck if you ever get it to work, unless you can find someone that has the
exact part and got it working already.
The only other thing i can think of at the moment is to contract the manufacturer and
ask for a data sheet, if that is possible.

Sorry i dont have anything else to suggest right now. The initialization routine for a
given part can be very different although there is sometimes a common pattern used
for the pin functions...but you never know there either.
LEDs vs Bulbs, LEDs are winning.

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rebeltaz
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Re: possible help using a vacuum flourescent display?

Post by rebeltaz » Thu Sep 10, 2009 8:50 am

The datasheet is the datasheet that the manufacturer provided me for this custom board. I only meant that the self-test routine described in the datasheet was inadvertently left in from the original design.

Thanks...
Derek Tombrello
http://www.ShelbyCycle.com

http://www.RobotsAndComputers.com

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haklesup
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Re: possible help using a vacuum flourescent display?

Post by haklesup » Thu Sep 10, 2009 4:02 pm

How about the basics like common ground between the module and the serial port. 1 and 0 don't mean a thing if the PC and the module have completely different ground voltages. Just a thought but something like that would turn the digital signals to gibberish.

Are all the DC voltages around the display what you would expect when its powered up. Do elements of the display light up, just not as you expect? In other words the DC-DC,AC supply for the display is not at fault.

That note under 4.2 is reassuring isn't it? One bad code and its garbage until you power off/on I suppose.

Also heed section 4.5. TTL serial voltage needs to be at least 2.4V for VIH and data needs to be configured 8,n,2 (default serial ports are usually 8,n,1). Don't forget that extra stop bit.

Finally the Caution under 5.1 might just be the nail in the coffin so to speak. If somebody operated the serial port while the module was powered off, the serial input pin might be toast.

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