I came across some old LCD displays which wasn’t equipped with a display controller but only the LCD driver circuits. The label on the display read ‘LMG7410PLFC-A’ but I only got a hit matching ‘LMG7400PLFC’. This is the display which has the controller chip on and that datasheet are quite firm on the fact that one should not use CN3 for connections. Being the only connector with pins soldered to it, I figured that the display might be working without the controller parts.
First thing was to figure out the pinout. From the datasheets of the drivers (LC7940N and LC7942N) and probing around on the board the following pinout is found:
| Pin # | Function |
|---|---|
| 1 | Hdata |
| 2 | VData |
| 3 | Display_off (Active low) |
| 4 | LOAD |
| 5 | Clock |
| 6 | N.C. |
| 7 | VDD (5V) |
| 8 | VSS (0V) |
| 9 | VEE (-15) - currently working fine with -10V |
| 10 | V0 (Tied to pin 8) |
Sooo.. did you get it work with an ardiuno? (if that even makes sense). We have a bunch of them at Labitat (labitat.dk – everyone is welcome), and it could be fun if they could be used for a project of some sort..
I got mine from Labitat as well 😉
I have not been able to get a stable image yet. I have been quite busy on ‘real’ work but I have a plan to get it to work with the Stellaris launchpad since that processor should have just enough RAM to make a framebuffer work.
I plan to make a small ‘todays appointments’ wit ha feed from my google calendar, but that requires of course that the screen is working 😉