M38203M4 Datasheet, PDF (253/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.7 LCD drive control circuit
Continued from Figure 2.7.7
Setting of LCD mode register
Select count source, bias, or others
b7
b0
0
LM: LCD mode register [Address 3916]
b1, b0: Duty ratio selection bits
b1b0
00: Not used
01: 2 (use COM0, COM1)
10: 3 (use COM0–COM2)
11: 4 (use COM0–COM3)
b2: Bias control bit
0: 1/3 bias
1: 1/2 bias
b3: LCD enable bit
0: LCD OFF
1: LCD ON
b4: Fix this bit to “0”
b6, b5: LCD circuit divider division ratio selection bits
b6b5
00: LCDCK count source
01: 2 division of LCDCK count source
10: 4 division of LCDCK count source
11: 8 division of LCDCK count source
b7: LCDCK count source selection bit
0: f(XCIN)/32
1: f(XIN)/8192
ŽSetting display data into the RAM (Address 4016 to 5316) for
LCD display
By writing “1” to bits in the RAM for LCD display, the corresponding
segments of the LCD panel becomes ready for lighting
Fig. 2.7.8 Example of setting registers for LCD display (2)
3820 GROUP USER’S MANUAL
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