Finding out the pin config od a 42pin unmarked LCD

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Ogive

Joined: 27 Mar 2007
Posts: 17

27 Mar 2007 16:54 Finding out the pin config od a 42pin unmarked LCD

Hi

I have recently bought a 42 pin unmarked LCD. It looks like a dot matrix but I can't be sure. IT has PDIP pins. Is there any way of finding out how it works without damaging it?

cameo_2007

Joined: 15 Mar 2007
Posts: 439
Helped: 17
Location: 13.04°N80.17°E

28 Mar 2007 13:00 Finding out the pin config od a 42pin unmarked LCD

try finding out if something is written anywhere in the board.i mean part number?

cyberrat

Joined: 19 Jun 2001
Posts: 966
Helped: 40
Location: In the sewers of the U.K.

28 Mar 2007 16:03 Finding out the pin config od a 42pin unmarked LCD

Can you show a close up picture of it?

Ogive

Joined: 27 Mar 2007
Posts: 17

28 Mar 2007 17:06 Re: Finding out the pin config od a 42pin unmarked LCD

There are no markings on the LCD itself so I am posting a picture of it. Anybody knows if there is some kind of a general way for finding out the pins? Just like there is for LEDs...

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on1aag

Joined: 30 Jun 2006
Posts: 155
Helped: 36

29 Mar 2007 1:56 Re: Finding out the pin config od a 42pin unmarked LCD

Hi Ogive,

You can try to test it with a 30 Hz oscillator.

Finding out the pin config od a 42pin unmarked LCD

And see what it does.

Finding out the pin config od a 42pin unmarked LCD

Once you've managed to get something on the display you know
that you've found the backplane and you can easely find all other
characters.
However there can be more than one backplane. Shocked