78 Chapter 2: TI-83 Plus Specific Information
TI-83 Plus Developer Guide Third Release May 28, 2002
Bottom Row
LD A,0BFh ; last row
CALL lcd_busy_2
OUT (lcdinstport),A
Column (Y) addressing
Commands 20h to 2Bh — sets the column address to 0 – 0Ch.
First byte of row
LD A,20h ; first byte of row
CALL lcd_busy_2
OUT (lcdinstport),A
Last byte of row
LD A,2Bh ; last byte of row
CALL lcd_busy_2
OUT (lcdinstport),A
– Setting auto addressing modes. The driver can act in four different ways after a
read or write.
Command 05h — X Direction auto increment
Command 07h — Y Direction auto increment
Command 04h — X Direction auto decrement
Command 06h — Y Direction auto decrement
The TI-83 Plus system expects the driver to be in X-increment mode and must
be set to this mode before giving control to the system.
• Reading the Contents of the Display Driver RAM
CALL lcd_busy_2
IN A,(lcddataport) ; read disp byte that X and Y
; settings point to