hello guys
i've got an lcd with 12864A written on its back & no more details is available
so how to know what kind of LCD is tht to start work with it ?
Last Edited: Wed. Mar 28, 2018 - 09:26 AM
LCD labelled 12864A help requested
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What's the controller chip got written on it?
What connections does it have?
Photo?
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johnny22 wrote:
to start work
So what is the goal here:
- To get some work done?
- To play around - possibly for a significant time - reverse-engineering this unknown product?
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As Brian says the key thing is the controller. A lot of the cheap and cheerful ones on ebay are KS0108 based. If so there is some polish software I've used in the past that seems quite good:
http://en.radzio.dxp.pl/ks0108/
But you do need to identify the controller chip to know if this is relevant
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Simply putting "12864A" into Google gives many relevant-looking hits; eg,
https://www.elecrow.com/download/SPE_IM120424014_EONE_12864_Graphic_LCD.pdf
and:
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Unfortunately there are just too many things out there labelled "12864A". As almost all LCD of this aspect ratio are 128x64 resolution then the "12864" bit is inevitable, so only "A" is really a differentiator, but it's too widely used too. If the module has chip-on-board ICs under anonymous black blobs (as in that picture) then trying to determine the controller type could prove "fun"! But even if you do you still probably need the datasheet for the "module" as well as the "controller" simply to know the pin out on the edge connector.
I have used several 12864 modules over the years and although many use the same number of pins (20), the pinouts can vary significantly.
Several years ago I had to design a module to allow use of some of those devices and found the following signal possibilities (not exhaustive):
Note the different power pinouts as well as signal placement...
Last Edited: Wed. Mar 28, 2018 - 02:02 PM
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Well, the images are certainly very similar, though not quite the same:
Perhaps try a Google Image Search on your photo - in various rotations ... ?
sure i want to use it for a project
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awneil wrote:
So what is the goal here:
- To get some work done?
- To play around - possibly for a significant time - reverse-engineering this unknown product?
johnny22 wrote:
would you check plz?
So maybe there should be a third option in the list:
- Get someone else to reverse-engineer it for you
awneil wrote:
awneil wrote:So what is the goal here:
- To get some work done?
- To play around - possibly for a significant time - reverse-engineering this unknown product?
johnny22 wrote:would you check plz?
So maybe there should be a third option in the list:
- Get someone else to reverse-engineer it for you
im just using this LCD for first time & any help will be appriciated
Go on. It is 99.9% obvious that you have a regular KS0108 display.
Try it for yourself. Report back with the result(s).
David.
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johnny22 wrote:
im just using this LCD for first time
https://www.avrfreaks.net/commen...
EDIT
So you've tried to save yourself a few quid by buying an unidentified, undocumented, unsupported module - that's a risk.
As David says, you're just going to have to take a risk and try it ...
Last Edited: Wed. Mar 28, 2018 - 04:32 PM
Looks like it has the Adafruit 188 pinout, with the KS0108 controller.
You should be able to connect it and use the appropriate library without too much difficulty...
(famous last words! 
)
johnny22 wrote:
sure i want to use it for a project
1) How much time have you spent on this quest of using an unknown LCD?
1a) Do you even know if it works?
1b) ...if not, how will you know when it is not working?
2) How much does a known-quantity 128x64 monochrome display cost? A new one with known provenance and excellent chance of being operational?
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Yes - that was exactly my point in #3 !
EDIT
I don't see any mention at https://www.ebay.com/itm/12864B-... of what controller is used.
Nor any sample code, tutorials, etc.
As opposed to, say, https://www.adafruit.com/product... - for the extra $20, you get it mounted on a breadboard-friendly PCB with documentation, support, and examples
Last Edited: Wed. Mar 28, 2018 - 07:00 PM
awneil wrote:
for the extra $20, you get it mounted on a breadboard-friendly PCB with documentation, support, and examples
If it were not: OUT OF STOCK
awneil wrote:
I don't see any mention at https://www.ebay.com/itm/12864B-... of what controller is used. Nor any sample code, tutorials, etc.
Ummm--in some part, that was intentional to elicit responses from OP that are the same as yours...
Go on. KS0108 displays are pretty straightforward. They have multiple CS pins e.g. CS1, CS2 for a 128x64. CS1, CS2, CS3 for a 192x64.
Normally the CS are active-high. Sometimes they are active-low e.g. /CS1
The pcb side should have the right number of components and blobs as a typical KS0108.
If the terminal pins are marked e.g. DB3, CS2, ... you can compare the wiring too.
David.
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was the KS0108 not also more or less standardized? Like the HD44780. a lot of different controllers around, but they can all be addressed as being a HD44780 and they will just behave like one if you stay inside the more standard commands.
so giving it a try using a KS0108 driver will not destroy it. what you could do is first find out what the supply pins are ( Not fully read all the comments) these you then can connect. then add 1K series resistors on all the other lines. that should keep ins from being destroyed by accidental shorts.
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In the past I think I've paid something like $5 for a 128x64 from a known source with documentation. That might actually be the easiest answer!