Specifications

S1C62N82 TECHNICAL SOFTWARE EPSON II-35
CHAPTER 3: PERIPHERAL CIRCUITS (LCD Driver)
SEG0 SEG1 SEG2 SEG3 SEG37
COM0 ■■D0 ■■D0 ■■D0 ■■D0 ■■D0
COM1 ■■D1 ■■D1 ■■D1 ■■D1 ■■D1
COM2 ■■D2 ■■D2 ■■D2 ■■D2 ■■D2
COM3 ■■D3 ■■D3 ■■D3 ■■D3 ■■D3
COM4 ■■D0 ■■D0 ■■D0 ■■D0 ■■D0
COM5 ■■D1 ■■D1 ■■D1 ■■D1 ■■D1
COM6 ■■D2 ■■D2 ■■D2 ■■D2 ■■D2
COM7 ■■D3 ■■D3 ■■D3 ■■D3 ■■D3
Memory address Data bit
• Bit-unit operation of the display memory
The LCD display routine using the assignment of Figure
3.6.5 can be programmed as follows.
Label Mnemonic/operand Comment
LD Y,090H ;Set address display memory
LD MY,3 ;SEG-A, B ON (●, ▲)
AND MY,1110B ;SEG-A OFF (●●, ▲)
AND MY,1101B ;SEG-B OFF (●●, ▲▲)
For manipulation of the display memory in bit-units for the
assignment of Figure 3.6.5, because the LCD RAM can be
read and written, so data can be changed directly using an
ALU instruction (for example, AND or OR).
• Displaying dot matrix LCD (for 8 commons)
The dot matrix LCD display routine using the assignment of
Figure 3.6.6 can be programmed as follows.
▲●
090H
D3 D2 D1 D0
Address
Data
▲
●
: SEG - A
: SEG - B
Fig. 3.6.5
Example of segment
assignment
DBH
DAH
91H
90H
93H
92H
95H
94H 96H .........
97H .........
↑
↑
Fig. 3.6.6 Dot matrix LCD assignment