How to test if it is a non-multiplexed (static) LCD?

Question

I got some static LCD's from an old cheap clock, calculator and the like and now I would like to use them for displaying simple things like temperature. They are connected with those pink with grey connector bars, if you know what I mean.

I found this article: http://www.ubasics.com/driving_static_lcds but he talks about non-multiplexed LCD's. How can I see/test/check what for static LCD I have?

It would be great if I could use these static LCD's, do you guys got more info on how to use these things (multiplexed or not)? Can I use it with an ATtiny2313?

Thanks.

Answer 1

You can hook up the LCD as described in that article, and start testing pins by hooking the common up to one pin, and the drive up to another pin. Map out the whole LCD this way and you should soon see which segments go to which pins.

A static LCD will have one pin, common, that will drive all other segments (should be easy to find) and another pin for each segment on the display.

A multiplexed display will have 2 or more common pins that each drive a number of segments, an each other pin will drive a few segments.

Answer 2

Try counting the number of pins compared to the number of LCD display segments? That should be one way to possibly determine. There should be at least as many pins as segments, plus a one or more extra for the common pin(s). If there are significantly fewer pins than display segments, it must be multiplexed.