ST7571 Datasheet, PDF (45/76 Pages) Sitronix Technology Co., Ltd. – 4 Gray Scale Dot Matrix LCD Controller/Driver

ST7571
9.1.27 Extension Command Set1
This instruction enables the extension command set-1.
A0
R/W
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
0
0
1
1
1
1
1
1
0
1
9.1.28 Extension Command Set2
This instruction enables the extension command set-2.
A0
R/W
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
0
0
1
1
0
1
0
0
0
1
9.1.29 Extension Command Set3
This instruction enables the extension command set-3.
A0
R/W
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
0
0
0
1
1
1
1
0
1
1
Extension Command Set 1
After entering the extension mode-1, the extension command set-1 is enabled. These commands are valid only in this
mode. Always remember to return back to normal mode for correct operation.
Increase Vop Offset
This instruction increases the Vop offset (Vof[4:0]) by 1.
A0
R/W
DB7
DB6
DB5
0
0
0
1
0
Decrease Vop Offset
This instruction decreases the Vop offset (Vof[4:0]) by 1.
A0
R/W
DB7
DB6
DB5
0
0
0
1
0
DB4
1
DB4
1
DB3
0
DB3
0
DB2
0
DB2
0
DB1
0
DB1
1
DB0
1
DB0
0
Fine Tune Vop
The “Increase Vop Offset” and “Decrease Vop Offset” instructions fine tune the voltage of Vop. The relation is shown below:
Note:
1. The range is limited. If continuously setting “Increase Vop Offset”, Vof[4:0] will increase. When Vof[4:0] is 0x0F and
followed by a “Increase Vop Offset” command, Vof[4:0] will become 0x10. As the result, Vop changes from +15 step
to -16 step. Software programmer should add a software protection to prevent that an operator maybe presses the
“Increase Button” too many times accidentally.
2. EV”[5:0] = EV[5:0] + Vof[4:0] and EV”[5:0] ≤ 0x3F. If EV[5:0] + Vof[4:0] > 0x3F, EV”[5:0] will truncate the invalid bit.
Ver 1.5a
45/76
2009/7/21