Re: [uCsimm] LCD connected, now what ???

From: Filip Peters (filip.peters@metris.be)
Date: Thu Sep 21 2000 - 08:33:13 EDT


Hello Ling,

I'm not Tom but I also use a LM32019, so maybe I can give some hints...

Ling Su wrote:

> Hi, Tom,
>
> I have some specific questions on LCD, hope you can help me, thanks.
>
> <1>.What is the resolution for ALPS LRHDD1012A?
>
> <2>. Right now I only have a Sharp LM32019 and its invertor, but I can not
> find the connector anywhere, Earthe computer won't help me since they think
> the order is too small, I guess. I am also looking for a 640x480 panel, do
> you think Epson EG9013 LCD is a good choice?
>

I have soldered a piece of flatcable with a normal press-on connector directly to the
cable end from the panel.
You shouldn't do this for a production piece, but for hobbyist use it's possible. The
end of the cable from the panel has tinned contacts so it's possible to solder it.
just make sure you don't solder too long otherwise the plastic melts. Warning! If you
don't have much soldering experience, let somebody else do it!

I've also tried the 9013 panel, but I found it flickered too much for me, the picture
on the lm32019 looks much nicer/stable. The 640by480 resolution is really stretching
the capabilities of the dragonball.
Of course some people are more (or less) sensitive to the flickering of a monitor, so
maybe it could be okay for you.

>
> <3>. For the LM32019 invertor, I can not find the document talking about the
> CN2 connector, there are five signal pins, what do they mean? How do I
> basically use the convetor?
>

You can look at the printed circuit board, you can see that you only need to connect
2 wires, gnd and +12V to get it to work. Tom has posted the correct polarity in one
of his previous post, so you can check that. (My simm is at home so I can't look at
the actual connection right now).

If you don't have the correct connector, solder 2 wires to it. All those special
connectors are sometimes hard to find. My local electronics shop doesn't stock them,
and ordering them with some online store mostly gives a lot of shipping costs, so I
improvise a lot for those special connections...

>
> <4>. The LM32019 need a 16V-20V power supply, usually how to make one?
>

A switching supply is the most elegant way, but you can also make it with a simple
regulator ic like a lm317. Use an 18v transformer, and calculate the resistors for
your range. A supply with an lm317 can be made in about half an hour.
It needs to be variable since it regulates the contrast, but it should go to around
22V, mine lm32019 doesn't give a picture under 20V...
You could also use a fixed supply of around 21V and let the processor do the contrast
control (see one of the appnotes on motorola's site), but in the testing phase it's a
lot easier to have a potentiometer to regulate the contrast.

Filip.

>
> Thanks a lot!
>
> Regards,
> -Ling
>
> This message resent by the ucsimm@uclinux.com list server http://www.uClinux.com/

--
Ir. Filip Peters
fp@metris.be

This message resent by the ucsimm@uclinux.com list server http://www.uClinux.com/



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