ST7920
l
Extended Function Set
RS RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
0
1
DL
X
RE
G
X
Code
DL: 4/8-bit interface control bit
When DL = "1", 8-bit MPU interface.
When DL = "0", 4-bit MPU interface.
RE: extended instruction set control bit
When RE = "1", extended instruction set
When RE = "0", basic instruction set
G: Graphic display control bit
When G = "1", Graphic Display ON
When G = "0", Graphic Display OFF
In same instruction cannot alter DL, RE and G at once. Make sure that change DL or G first and then RE.
l
Set Scroll Address
RS
0
RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
1
AC5 AC4 AC3 AC2 AC1 AC0
Code
SR=1: AC5~AC0 is vertical scroll displacement address
Set Graphic RAM Address
l
RS
0
RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
AC5 AC4 AC3 AC2 AC1 AC0
Code
Code
RS
0
RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
0
AC3 AC2 AC1 AC0
Set GDRAM address into address counter (AC). This is a 2-byte instruction.
The first instruction sets the vertical address while the second one sets the horizontal address (write 2
consecutive bytes to complete the vertical and horizontal address setting).
Vertical address range is AC5...AC0
Horizontal address range is AC3…AC0
The address counter (AC) of graphic RAM (GRAM) will be increased automatically after the vertical and
horizontal addresses are set. After horizontal address is increased upto 0FH, it will automatically return to 00H.
However, the vertical address will not increase as the result of the same action.
V4.0
24/49
2008/08/18
SITRONIX [ SITRONIX TECHNOLOGY CO., LTD. ]
