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Unknown LCD pin outs mapping related

pasc

Feb 4, 2016
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Hi guys a newbie here
tongue.gif
, i'm doing a project with an unknown multiplexed LCD, i don't know any of its caracteristics besides its a 16x3 LCD with 33 pins, i'm trying to do the pins mapping but i'm not succeeding at this :/, i've tried several things i'm running out of ideas of how to do the mapping of the LCD pins i'm including two pictures of the LCD, one of the pictures the LCD has almost all segments displaying, any help of any kind is very much appreciated, thank you in advanced for help.
 

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dorke

Jun 20, 2015
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Well,
Where was it pulled from?
if you know that it may help you.

Surely you don't need all the "dedicated" symbols on it,
maybe just the numerical display?
If so, it would be easier to get a known LCD to work with.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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What you need to do is to map out the pins to determine which is used for what (this applies if you can't find data for the display)

first you create a small circuit which produces the typical drive voltages for an LCD display, then you use it to probe pairs of pins.

The circuit will require a 40106 cmos Schmitt trigger with one of the gates configured as an oscillator at a frequency of about 80Hz. The remaining 5 gates are wired as one string of 3 and one string of 2, with the inputs connected to the oscillator output. The outputs are connected to 4k7 resistors, and the other ends of the resistors connected to your probed (relax, I'll draw it for you later :)).

this circuit produces the type of AC signal that SHOULD be safe to drive the display.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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This is what I mean :)

LCD_Tester.png
 
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