LCD 16X2

[meduino]

[https://docs.google.com/file/d/0B9Y41MEm02L9NlBRMV81WlZuemc/edit?usp=sharing
https://docs.google.com/file/d/0B9Y41ME ... sp=sharing][/url]
Hello,
I have some salvaged 16X2 LCD modules I would like to use. They are made by the Three-Five. I have been googling the HY-238, 5000-0030-01, 9000-0020-05 without any luck. Searching the Three-Five website is not returning any info. My Q is how to identify the module. The control chip has black hard material over it, so no numbers are readable. Any ideas?
thank you

[floresta]

My Q is how to identify the module.

You can see the module and you are having trouble identifying it so imagine the trouble that we are having....

Don

[adafruit_support_mike]

What you're looking at is an COB (Chip On Board) package where the silicon die is physically glued to the PCB. Contact wires are run from the die to pads on the PCB, and the whole thing is potted in epoxy to protect the chip.

Identifying those tends to be more of a reverse-engineering project than a document search. Many such chips are made especially for the vendors, or are things where you only get a datasheet if you buy in bulk and sign a nondisclosure agreement.

The usual way to learn how such chips operate is to put them in the original system, connect all the leads to a logic analyzer, and watch the traffic while the system starts up and displays data. Certain processes become familiar after a while, so you learn to spot delays while charge pumps warm up, SPI traffic, etc. Then you dig through the datasheets you do have for devices that might be similar, make some more educated guesses, and write a bunch of test code.

There's no single-and-easy way to get a datasheet though.

[floresta]

You can see the module and you are having trouble identifying it so imagine the trouble that we are having....

Now you make me look like an idiot because you went back and modified your original post to include the formerly missing link. Thanks a lot.

Don

[meduino]

You can see the module and you are having trouble identifying it so imagine the trouble that we are having....

Now you make me look like an idiot because you went back and modified your original post to include the formerly missing link. Thanks a lot.

Don

Don,
please do not consider my negligence too important. I have been feeling like an idiot since I started to learn the electronics and posting dum Q. I was hoping that the numbers I included would help without an image. thank you for responding anyway.
thank you mstone! I will consider to purchase new lcd module

[tldr]

well, it's got 16 pins. there may well be an hd44780 under the blob. does there appear to be a backlight on it? if you can locate the pins that control the backlight, you could start to make some informed guesses as to what the other pins are.

[floresta]

well, it's got 16 pins. there may well be an hd44780 under the blob.

I think the 16 pins may be a coincidence. I'm inclined to think there is an HD44780 under there as well but I suspect the interface to the outside world is likely to be some sort of serial implementation.

Don

[tldr]

if it does use a serial protocol, then the same signals are probably brought out to both headers. a little continuity check ought to suffice.