SPC8104 S-MOS Systems, SPC8104 Datasheet - Page 147

• Manufacturer Part Number: SPC8104
• Description: VGA LCD CONTROLLER
• Manufacturer: S-MOS Systems

Appendix B POWER SAVE MODE DESCRIPTIONS
To accommodate the important need for power reduction in sub-notebook and palmtop comput-
ers, three Power Save Modes, Doze mode 1, Doze mode 2, and Suspend, have been incorpo-
rated into the SPC8104. All Power save modes are software-controlled or hardware-controlled.
Additional options for these Power Save Modes can be enabled by setting bits in various Auxiliary
registers, allowing flexibility in tailoring the power reduction scheme to any particular system
implementation.
Suspend mode can be activated through input pin SUSPEND# or by enabling the Suspend Mode
Enable bit in the Power Save Register (AUX[03]). There are some small differences between
hardware Suspend mode and software Suspend mode. Hardware Suspend mode will override
software Suspend mode. Doze mode can be activated through input pin DOZE# or by enabling
the Doze Mode Enable bit. The Doze mode select bits determine the function of the Doze mode.
Hardware Doze mode and software Doze mode are functionally identical. Whether hardware acti-
vated or software activated, Suspend mode always overrides Doze mode.
SPC8104
412-1.0
Slow Pixel Clock
Reduce Palette
Display off
Display Memory Read/Write
Backlight Off
Relative Power Saving
S-MOS Systems, Inc. • Tel: [phone] • Fax: [phone] • http://www.smos.com
Operation)
(Normal
State 0
None
Yes
No
No
No
No
(Doze 1)
State 1
X15-SP-002-03
Low
Yes
Yes
No
No
No
(Doze 2)
State 2
High
Yes
Yes
Yes
No
No
(Suspend)
Stopped
State 3
Highest
N/A
Yes
Yes
No
BIOS Functional Specification
SP2-41