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Electronics => Beginners => Topic started by: frenky on January 15, 2013, 09:41:03 pm

Title: Bare lcd signal?
Post by: frenky on January 15, 2013, 09:41:03 pm

Hi guys.

I'm trying to put big 7 segment display on the kitchen scale that currently has small numeric LCD.
I was hoping that I could catch the value going to the eeprom but sadly it doesn't use eeprom during measurement.

So the only way to get the value is to read data from LCD pins.
LCD has 4 digits, 3 dots and some other signs (battery low + 2 other)
It uses 14 pins. One is ground and the other 13 have some odd signal (picture below).
I'm sure it's not odd for you guys so please point me into the right direction on how to decode this signals.  ;)

Wave form and kitchen scale below:

Title: Re: Bare lcd signal?
Post by: Bored@Work on January 15, 2013, 11:16:52 pm

This http://www.atmel.com/Images/doc2530.pdf (http://www.atmel.com/Images/doc2530.pdf) describes among other things how such LCD glasses are driven.

Title: Re: Bare lcd signal?
Post by: frenky on January 15, 2013, 11:18:48 pm

Tnx :)

I have also found something that helps: http://www.nxp.com/documents/data_sheet/PCF8576C.pdf (http://www.nxp.com/documents/data_sheet/PCF8576C.pdf)