I AM NEW TO INTARFACING VARIOUS DEVICES TO THE MICROCONTROLLER. I AM USING THE AT89C51 CONTROLLER I AM INTARFACING THE LCD WITH IT AND I AM USING PORT 2 AS THE DATA PORT PORT 0 PINS 5,6&7 CONNECTED RESPECTIVELY TO PIN 4,5&60F THE LCD.I HAVE LOADED THE PROGRAM OF IN CONTROLLER IS CHECKING THE BUSY BIT I.E.G. OF CHECKIG THE BUSY BIT BY POLLING. THE LCD IS NOT DISPLAYING ANY THING. I AUESS IT IS BEING INTIALIZED BUT IT IS NOT COMING BACK FROM THE SUBROUTINE OF POLLING. PLEASE HELP ME AS SOON AS POSSIBLE .
As others should state, please check the contrast. Some (at least most of them) use -VEE supply for the contrast. The typical voltage of the contrast ranges from 0V to -9V. At 0V the display is all white and nothing can be read; and @ -9V the display is all black and again nothing can be read. The values in between provide a change in the contrast. You can connect a linear pot (say 10K) between the -VEE of the LCD and -9V of the supply. Adjust the contrast.
check this website for more information
microcontroller51.blogspot.com/
ZEUISTI
CAN YOU HELP ME AGAIN?
I WANT TO SHOW DIFERENT CHARACTERS AND POSSIBLY SOME GRAPHICS.
HOW CAN I DO IT?
How about starting with lower-case ones...?
Erik would say: "the deaf leading the blind".
yes. i will try to help you.
this is code to program the characters. be care full! you Must change the DB's.
;**************************************************************************** ; ; TABLE OF CHARACTERS. 8 BYTES FOR EACH CHARACTER AND 8 CHARACTERS ; ;**************************************************************************** CHARS: DB 1Ah,25h,1Ah,25h,1Ah,25h,1Ah,00h DB 25h,1Ah,25h,1Ah,25h,1Ah,25h,00h DB 1Ah,25h,1Ah,25h,1Ah,25h,1Ah,00h DB 25h,1Ah,25h,1Ah,25h,1Ah,25h,00h DB 1Ah,25h,1Ah,25h,1Ah,25h,1Ah,00h DB 25h,1Ah,25h,1Ah,25h,1Ah,25h,00h DB 1Ah,25h,1Ah,25h,1Ah,25h,1Ah,00h DB 25h,1Ah,25h,1Ah,25h,1Ah,25h,00h ;**************************************************************************** ; ; LOAD CHARACTERS TO DISPLAY ; ;**************************************************************************** LOAD_CHARS: MOV A,#01000000B ;SAY CG RAM ADDR (0) CALL WRITE_CTRL MOV DPTR,#CHARS ;GO TO START OF DATA MOV R2,#64 ;WRITE 64 BYTES OF DATA LOOP1: CLR A MOVC A,@A+DPTR CALL WRITE_DATA INC DPTR DJNZ R2,LOOP1 RET
Master Zeusti
the man whith advice
A MASTER ZEUSTI,
YOURE CODE WORKS JUST ONLY A LITTLE CHANGE.
YOU ARE THE MAIN MAN!
THANK TO YOU AGAIN.