Lvds Backlight Brightness Control - MSI MS-98J8 User Manual

GPIO WDT BKL Programming

LVDS Backlight Brightness Control

3. LVDS Backlight Brightness Control
The LVDS controller support 17 level of backlight brightness value from 0 (30%) to 16 (100%) and it is
accessible through SMBus. The associated access method (SMBus_ReadByte, SMBus_WriteByte) are
provided in part 4.
3.1 Set the Level of LVDS Backlight
1. Write 0xED into address 0x7F on SMBus device 0x42.
2. Write desired backlight level from 0x0 (30%) to 0x10 (100%) into address 0x6E on SMBus device 0x42.
Example: Set LVDS backlight level to 0x10 (100%)
SMBus_WriteByte (0x42, 0x7F, 0xED);
SMBus_WriteByte (0x42, 0x6E, 0x10); // Set brightness to 100%
3.2 Read the Level of LVDS Backlight
1.Write 0xED into address 0x7F on SMBus device 0x42.
2.Read current backlight level from address 0x6E on SMBus device 0x42.
Example: Get LVDS backlight level
SMBus_WriteByte (0x42, 0x7F, 0xED);
BKL_Value = SMBus_ReadByte (0x42, 0x6E);
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