A83: 83 lcd driver
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A83: 83 lcd driver
Here is some information on controlling the display
driver in the 83.
LCD DRIVER OPERATION TOSHIBA T6A04
20h y direction 2Bh
___________________________________
80h | | | | ... | |
|-----------------------------------
x |
direction |
|
|___________________________________
| | | | |
BFh |___________________________________
- INTERRUPTS MUST BE DISABLED TO SEND COMMANDS/DATA TO THE DRIVER
- THE DRIVER CAN BE IN 2 MODES AFTER A READ/WRITE
- X DIRECTION INCREMENT
- Y DIRECTION INCREMENT
- 83 SYSTEM EXPECTS THE DRIVER TO BE IN X-INCREMENT MODE
SO IF YOU CHANGE THAT CHANGE IT BACK BEFORE GIVING CONTROL
TO THE SYSTEM.
- A DELAY IS NEEDED BETWEEN EACH COMMUNICATION WITH THE DRIVER
WE MAKE A CALL TO THIS ROUTINE :
LCD_BUSY::
PUSH AF
inc hl
dec hl
POP AF
RET
LCDINSTPORT = 10h COMMAND PORT
LCDDATAPORT = 11h DATA PORT
COMMANDS
--------
LD A,07H
B_CALL LCD_BUSY
OUT (LCDINSTPORT),A ; SET TO Y INC MODE
LD A,05H
B_CALL LCD_BUSY
OUT (LCDINSTPORT),A ; SET TO X INC MODE
LD A,20H
B_CALL LCD_BUSY
OUT (LCDINSTPORT),A ; SET TO 1ST Y COL
LD A,80H
B_CALL LCD_BUSY
OUT (LCDINSTPORT),A ; SET TO 1ST X ROW
B_CALL LCD_BUSY
OUT (LCDDATAPORT),A ; WRITE BYTE TO DISP
B_CALL LCD_BUSY
IN A,(LCDDATAPORT) ; READ DISP BYTE
;
!!!! READING THE DISPLAY DRIVER AFTER SETTING X OR Y COORDINATE
- A DUMMY READ NEEDS TO BE DONE AFTER SETTING EITHER
THE X OR Y COORDINATE OF THE DRIVER IF YOU WANT TO
READ FROM THE DRIVER.
- IF YOU ARE GOING TO WRITE TO THE DRIVER THEN NOTHING
NEEDS TO BE DONE.