Signal Description
• MRL#: Manually operated retention latch sensor input. A logic low input that is connected
directly to the MRL sensor. When asserted it indicates that the MRL latch is closed. If a
platform does not support MRL sensors, this must be wired to a low logic level (MRL closed).
• ATTENTION BUTTON#: Signal connected to the PCI slot’s attention button. When low,
indicates that the operator has requested attention. If an attention button is not implemented,
then this input must be wired to a high logic level.
2.13.4
Serial Mode Operation
During Serial mode operation, the Intel® 6702PXH 64-bit PCI Hub sends and receives information
serially from the slot control logic. The slot control logic is required to deserialize the output
information to the bus switches and slot. The Slot control logic is also required to convert parallel
input information from the slots into serial data to the Intel® 6702PXH 64-bit PCI Hub. The serial
interface will run at 16.5 MHz. In this mode, the Intel® 6702PXH 64-bit PCI Hub constantly polls
the slot inputs, serially looking for an event at any of the hot plug slots. The output serial stream
from the Intel® 6702PXH 64-bit PCI Hub is on-demand and is only sent when the
Intel® 6702PXH 64-bit PCI Hub needs to schedule an event at a slot.
2.13.4.1
Serial Input Stream
The input stream shifted out by the Intel® 6702PXH 64-bit PCI Hub consists of 48 bits and is
fixed. If the board implements less than 6 slots in serial mode, a bit stream value of 1 must be
shifted into the Intel® 6702PXH 64-bit PCI Hub for the slot locations not implemented. The
sequence is shown below. Since the control bits corresponding to a slot are clustered into a group
and the control bits for slot 1 come last, the Intel® 6702PXH 64-bit PCI Hub does not support
stutter mode.
Table 2-25. Serial Input Stream (Sheet 1 of 2)
Bit#
Value
Bit#
Value
1
2
Slot1_ATTNB
Slot1_MRL
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Slot4_ATTNB
Slot4_MRL
3
Slot1_PWRFLT
Slot1_PRSNT1
Slot1_PRSNT2
Slot1_PCIXCAP1
Slot1_PCIXCAP2
Slot1_M66EN
Slot2_ATTNB
Slot4_PWRFLT
Slot4_PRSNT1
Slot4_PRSNT2
Slot4_PCIXCAP1
Slot4_PCIXCAP2
Slot4_M66EN
Slot5_ATTNB
4
5
6
7
8
9
10
11
12
13
14
15
16
Slot2_MRL
Slot5_MRL
Slot2_PWRFLT
Slot2_PRSNT1
Slot2_PRSNT2
Slot2_PCIXCAP1
Slot2_PCIXCAP2
Slot2_M66EN
Slot5_PWRFLT
Slot5_PRSNT1
Slot5_PRSNT2
Slot5_PCIXCAP1
Slot5_PCIXCAP2
Slot5_M66EN
Intel® 6702PXH 64-bit PCI Hub Datasheet
47
INTEL [ INTEL ]
