Registers Controlling Lcd Controller/Driver - NEC Renesas mPD71312 User Manual

3.4 Registers Controlling LCD Controller/Driver

The following four registers are used to control the LCD controller/driver.
• LCD mode setting register (LCDMD)
• LCD display mode register (LCDM)
• LCD clock control register (LCDC)
• LCD voltage boost control register 0 (VLCG0)
(1) LCD mode setting register (LCDMD)
LCDMD sets the number of segments and the LCD reference voltage generator.
LCDMD is set using an 8-bit memory manipulation instruction.
Reset signal generation sets LCDMD to 00H.
After reset:
Address: LCDCTL's 00H
Symbol 7
LCDMD SEGSET2 SEGSET1
SEGSET2 SEGSET1
0
0
Other than above
MDSET1 MDSET0
0
0
1
Cautions 1. Bits 2 to 4 must be set to 0.
2. LCDMD can be set only once after a reset release.
22
CHAPTER 3 LCD CONTROLLER/DRIVER
Figure 3-5. Format of LCD Mode Setting Register
00H R/W
6 5
SEGSET0
SEGSET0
1 1 36 (52-pin product)
×
0 40 (64-pin product)
Setting prohibited
0 External resistance division method
1 Internal resistance division method
×
Internal voltage boosting method
User's Manual U18438EJ2V0UD
4 3
0 0
Segment number setting
LCD reference voltage generator selection
2 1
0 MDSET1 MDSET0
0