Controlling RA6963 240x128 LCD with pic 16f877a

ToperaGarimpero · Joined: 29 Apr 2022 Posts: 1

Hello, I have been trying to make a Chinese lcd module to work, but so far, not even the contrast is working.

I'm using the code and libraries from this old post:

http://www.ccsinfo.com/forum/viewtopic.php?t=49389&highlight=t6963

And the lcd's pinout is in this chart.

https://imgur.com/a/PqYW1HW

One issue that I've found is that there's no negative voltage on Vee, and using an external power supply doesn't seem to make the contrast potentiometer to work.
Does anyone know what I could've been doing wrong?

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

Post a link to the data sheet for the LCD. Or the website for it.

temtronic · Posted: Fri Apr 29, 2022 2:46 pm

YES, need to KNOW what LCD module it is.. !!
Is it JUST the actual chip or a premade PCB with LCD,controller and 'connections' ??
I downloaded a manual Vee is mentioned as YOu supply it.

No Vee ? maybe YOU have to supply it ??

Some modules actually have the VEE electronics onboard...some don't....

Ttelmah · Joined: 11 Mar 2010 Posts: 19506

Yes.
We need to know what the module actually 'is'.
The voltage needed for Vee, depends of the display technology involved.
I have seen units needing voltages between -10v, and +4v. In many
cases different colour versons of the same display will need massively
different voltages on this.
We can't actually help you unless you tell us the unit involved.

temtronic · Posted: Sat Apr 30, 2022 7:50 am

I had one that spec said it needed -19 volts. I 'borrowed' some electrons from the -15 for the op amps in that project..... Very Happy

The other possible problem is that's a 5 volt PIC, so IS the LCD module a true 5 volt device or really 3 volt Vdd with 5 v 'tolerant' I/O pins ??