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Revision 1.1
G
Core Logic Module
(Continued)
5.4.2.2
F1 Index 40h, Base Address Register 1 (F1BAR1), points
to the base address of where the ACPI Support registers
ACPI Support Registers
are located. Table 5-34 shows the I/O mapped ACPI Sup-
port registers accessed through F1BAR1.
Table 5-34. F1BAR1+I/O Offset: ACPI Support Registers
Bit
Description
Offset 00h-03h
P_CNT — Processor Control Register (R/W)
Reset Value: 00000000h
31:5
4
Reserved.
Always reads 0.
THT_EN (Throttle Enable).
When this bit is asserted, it enables throttling of the clock based on the CLK_VAL field (bits
[2:0] of this register).
0:
Disable.
1:
Enable.
If F1BAR1+I/O Offset 18h[8] =1, an SMI is generated when this bit is set.
Top level SMI status is reported at F1BAR0+I/O Offset 00h/02h[2].
Second level SMI status is reported at F1BAR0+I/O Offset 20h/22h[1].
Reserved.
Always reads 0.
CLK_VAL (Clock Throttling Value).
CPU duty cycle:
000: Reserved
010: 25%
001: 12.5%
011: 37.5%
3
2:0
100: 50%
101: 62.5%
110: 75%
111: 87.5%
Offset 04h
Note:
Reserved
Reset Value: 00h
This register should not be read.
It controls a reserved function of power management logic.
Offset 05h
P_LVL3 — Enter C3 Power State Register (RO)
Reset Value: xxh
7:0
P_LVL3 (Power Level 3).
Reading this 8-bit read only register causes the processor to enter the C3 power state. Reads of
P_LVL3 return 0. Writes have no effect.
The ACPI state machine always waits for an SMI (any SMI) to be generated and serviced before transfer into C3 power
state.
A read of this register causes an SMI if enabled: F1BAR1+I/O Offset 18h[11] = 1. (Default)
Top level SMI status is reported at F1BAR0+I/O Offset 00h/02h[2].
Second level SMI status is reported at F1BAR0+I/O Offset 20h/22h[4].
Offset 06h
SMI_CMD — OS/BIOS Requests Register (R/W)
Reset Value: 00h
7:0
SMI_CMD (SMI Command and OS / BIOS Requests).
A write to this register stores data and a read returns the last data
written. In addition, a write to this register always generates an SMI. A read of this register does not generate an SMI.
Top level SMI status is reported at F1BAR0+I/O Offset 00h/02h[2].
Second level SMI status is reported at F1BAR0+I/O Offset 20h/22h[0].
Offset 07h
ACPI_FUN_CNT — ACPI Function Control Register (R/W)
Reset Value: 00h
7:5
4
Reserved.
Must be set to 0.
INTR_WU_SL1.
Enables wakeup on enabled interrupts in sleep state SL1.
0: Disable wakeup from SL1, when an enabled interrupt is active.
1: Enable wakeup from SL1, when an enabled interrupt is active.
GPWIO_DBNC_DIS (GPWIO0 and GPWIO1 Debouncers).
Debounce settings for GPWIO0 (ball AC15) and GPWIO1 (ball
AE16). Selects the time that a high-to-low or low-to-high transition (debounce period) must be for GPWIO0 to be recog-
nized.
0: Debounce period is 15.8 msec. (Default)
1: Debounce period is 31 μs.
GPWIO2 is fixed at 31 μs.
Reserved.
Must be set to 0.
PWRBTN_DBNC_DIS (Power Button Debouncer).
Allow a high-to-low or low-to-high transition of greater than 15.8 msec
(debounce period) on PWRBTN# (ball AF15) before it is recognized.
0: Enable. (Default)
1: Disable.
3
2:1
0