Help me connecting a GLCD to arduino

Hello i am trying to connect an LCD i have found with arduino
it is driven by a LC7980 240x40 and ATMEL AT27c010 CMOS
and a LM324m
i traced the pinouts for it and here it is

1- LED A
2- LED K
3- MS - CONNECTED TO A RESISTOR TO RESET PIN ON THE LC7980
4- CS
5- connected to LM324M GND
6- RS
7- RW
8- RD(E)
9- DB0
10- DB1
11- DB2
12- DB3
13- DB4
14- DB5
15- DB6
16- DB7
17- connected to A13 pin on the atmel cmos
18- connected to A14 pin on the atmel cmos
19- connected to A15 pin on the atmel cmos
20- connected to A16 pin on the atmel cmos

i also found out the the MS pin on the LC7980 is connected to LM324m V+

datasheet for LC7980

i also found this library https://code.google.com/p/u8glib/
already have support for LC7981 which i think is very similar to what i have

if anyone could help me figure out how to connect it i will be grateful


Hi

I do not know the difference between the LC7981 and LC7980, so the following applies to the LC7981:

U8glib requires the following pins:

U8GLIB_LC7981_160X80(db0, db1, db2, db3, db4, db5, db6, db7, rd(e), cs, rs [, rw [, reset]])

Displays with the LC7981 controller require an extrernal contrast adjustment, which require -15V. You will not see anything without feeding this negative voltage into the contrast input of the display.

Oliver

Hello , Thank you very much for your reply i got the LCD working
like this :

1- LED A
2- LED K -Common GND
3- MS - VDD
4- CS
5- V0
6- RS
7- RW
8- RD(E)
9>16 - DB0>DB7

i used an ATX PSU for a negative -12V

only one thing i want to adjust the resolution to fit to my display 240x40
i am using this from the UG8lib

//U8GLIB_LC7981_240X64 u8g(8, 9, 10, 11, 4, 5, 6, 7,  18, 14, 15, 17, 16); 	// 8Bit Com: D0..D7: 8,9,10,11,4,5,6,7 en=18, cs=14 ,di=15,rw=17, reset = 16

but this is a 240x64 , what files in the lib that needs to be changed to adjust the display height

Thank you again for the help :slight_smile:

Very good.

In u8g_dev_lc7981_240x64.c change

#define HEIGHT 64

to

#define HEIGHT 40

Oliver