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LCD Controller
4-10
MC68328 DRAGONBALL PROCESSOR USER’S MANUAL
MOTOROLA
4.5.6 FRC Offset Control
4.5.7 Cursor and Blinking Rate Control
4.5.8 Low-Power Mode
Some panels may have a signal called PANEL_OFF that turns off the panel for low-power
mode. In the MC68328 processor system, this signal is not supported. Instead, use a paral-
lel I/O pin to perform this function.
The software sequence to achieve PANEL_OFF using parallel I/O consists of 2 steps:
1. Turn off the VLCD (+15V or -15V) by I/O driving a transistor
2. Turn off the LCDON bit
To exit from LCDC-off mode:
1. Turn on the LCDON bit
2. Delay for 1-2ms
3. Turn on the VLCD by I/O driving a transistor
When setting the LCDON bit (register CKCON bit 7) to 1, LCDC itself will enter a low-power
mode by stopping its own pixel clock prior to the next line-buffer-fill DMA. Additional screen
DMA and display-refresh operations will then be stopped in this mode. When the LCDC is
switched back on, DMA and screen-refresh activities will resume in a synchronous fashion.
Software should check that the actual PANEL_OFF signal is de-asserted before setting
LCDON to a 1.
Table 4-2. Gray Scale Code Mapping
Code Mapping
Data
Gray code
00
G02G01G00
01
G12G11G10
10
G22G21G20
11
G32G31G30
Table 4-3. Gray Palette Selection
Gray Palette
Gray Code
Density
000
0
001
1/4
010
5/16
011
1/2
100
11/16
101
3/4
110
1
111
1
Summary of Contents for DragonBall MC68328
Page 5: ...vi MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 25: ...Overview 1 14 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 45: ...System Integration Module 2 20 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 103: ...Parallel Ports 7 16 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 117: ...UART 8 14 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...
Page 127: ...SPI Master 10 6 MC68328 DRAGONBALL PROCESSOR USER S MANUAL MOTOROLA ...