Revision 1.1
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G
Core Logic Module
(Continued)
2
Re-trigger General Purpose Timer 1 on Parallel/Serial Port Activity.
0: Disable.
1: Enable.
Any access to the parallel or serial port I/O address range listed below reloads the General Purpose Timer 1:
— LPT3: I/O Port 3BCh-3BEh.
— LPT2: I/O Port 378h-37Fh.
— COM1: I/O Port 3F8h-3FFh (if F0 Index 93h[1:0] = 10 this range is excluded).
— COM2: I/O Port 2F8h-2FFh (if F0 Index 93h[1:0] = 11 this range is excluded).
— COM3: I/O Port 3E8h-3EFh.
— COM4: I/O Port 2E8h-2EFh.
Re-trigger General Purpose Timer 1 on Floppy Disk Activity.
0: Disable.
1: Enable.
Any access to the floppy disk drive address ranges listed below reloads General Purpose Timer 1:
— Primary floppy disk: I/O Port 3F2h-3F5h, 3F7h
— Secondary floppy disk: I/O Port 372h-375h, 377h
1
The active floppy disk drive is configured via F0 Index 93h[7].
Re-trigger General Purpose Timer 1 on Primary Hard Disk Activity.
0: Disable.
1: Enable.
Any access to the primary hard disk address range selected in F0 Index 93h[5], reloads General Purpose Timer 1.
0
Index 8Ah
General Purpose Timer 2 Count Register (R/W)
Reset Value: 00h
7:0
GPT2_COUNT.
This field represents the load value for General Purpose Timer 2. This value can represent either an 8-bit or
16-bit counter (configured in F0 Index 8Bh[5]). It is loaded into the counter when the timer is enabled (F0 Index 83h[1] = 1).
Once the timer is enabled and a transition occurs on GPIO7, the timer is re-loaded.
The counter is decremented with each clock of the configured timebase (1 msec or 1 sec selected at F0 Index 8Bh[3]).
Upon expiration of the counter, an SMI is generated and the top level of status is F1BAR0+I/O Offset 00h/02h[9]. The sec-
ond level of status is reported at F1BAR0+I/O Offset 04h/06h[1]). Once expired, this counter must be re-initialized by either
disabling and enabling it, or by writing a new count value in this register.
For GPIO7 to act as the reload for this counter, it must be enabled as such (F0 Index 8Bh[2]) and be configured as an input.
(GPIO pin programming is at F0BAR0+I/O Offset 20h and 24h.)
Index 8Bh
General Purpose Timer 2 Control Register (R/W)
Reset Value: 00h
7
Re-trigger General Purpose Timer 1 (GP Timer 1) on Secondary Hard Disk Activity.
0: Disable.
1: Enable.
Any access to the secondary hard disk address range selected in F0 Index 93h[4] reloads GP Timer 1.
Reserved.
Should be set to 0.
General Purpose Timer 2 (GP Timer 2) Shift.
GP Timer 2 is treated as an 8-bit or 16-bit timer.
0: 8-bit. The count value is loaded into GP Timer 2 Count Register (F0 Index 8Ah).
1: 16-bit. The value loaded into GP Timer 2 Count Register is shifted left by eight bits, the lower eight bits become zero,
and this 16-bit value is used as the count for GP Timer 2.
General Purpose Timer 1 (GP Timer 1) Shift.
GP Timer 1 is treated as an 8-bit or 16-bit timer.
0: 8-bit. The count value is that loaded into GP Timer 1 Count Register (F0 Index 88h).
1: 16-bit. The value loaded into GP Timer 1 Count Register is shifted left by eight bit, the lower eight bits become zero, and
this 16-bit value is used as the count for GP Timer 1.
General Purpose Timer 2 (GP Timer 2) Timebase.
Selects timebase for GP Timer 2 (F0 Index 8Ah).
0: 1 second.
1: 1 millisecond.
6
5
4
3
Table 5-29. F0: PCI Header and Bridge Configuration Registers for GPIO and LPC Support (Continued)
Bit
Description