Signal Description
2.5
Hot Plug Interface
There are two sets of hot plug interface signals, one for PCI Bus A and one for PCI Bus B.
Table 2-5. General Hot Plug Interface A and B Signals – All Hot Plug Modes
Signal
Type
Description
HPA_SLOT[3]
HPB_SLOT[3]
I
Enable/Disable PCI Hot Plug Mode:
1 = Hot Plug Mode Enabled
0 = Hot Plug Mode Disabled
HPA_SLOT[2:0]
HPB_SLOT[2:0]
I
Hot Plug Mode / # of PCI Slots: Used in conjunction with HPx_SLOT[3]
signal to determine PCI Hot Plug Mode and number of PCI slots on a bus
segment.
HPx_SLOT[3:0] = Hot Plug Mode Enable/Disable, # of PCI slots
0000 = hot plug disabled, 1 slot (optional)
0001 = hot plug disabled, 2 slots (optional)
0010 = hot plug disabled, 3 slots (optional)
0011 = hot plug disabled, 4 slots (optional)
0100 = hot plug disabled, 5 slots (optional)
0101 = hot plug disabled, 6 slots (optional)
0110 = hot plug disabled, 7 slots (optional)
0111 = hot plug disabled, 8 slots (optional)
1000 = reserved
1001 = hot plug enabled, 1 slot (parallel mode)
1010 = hot plug enabled, 2 slots (parallel mode)
1011 = hot plug enabled, 3 slots (serial mode)
1100 = hot plug enabled, 4 slots (serial mode)
1101 = hot plug enabled, 5 slots (serial mode)
1110 = hot plug enabled, 6 slots (serial mode)
1111 = hot plug enabled, 1-slot-no-glue (parallel mode)
Table 2-6. Serial Mode Hot Plug Signals – Interface A and B – 3 to 6 Slots (Sheet 1 of 2)
Signal
Type
Description
HPA_SLOT[3:0]
HPB_SLOT[3:0]
I
Hot Plug Mode Enable / # of PCI Slots: Used to enable/disable hot plug
mode and to determine number of hot plug slots.
HPx_SLOT[3:0]:
1011 = hot plug enabled, 3 slots (serial mode)
1100 = hot plug enabled, 4 slots (serial mode)
1101 = hot plug enabled, 5 slots (serial mode)
1110 = hot plug enabled, 6 slots (serial mode)
HPA_PRST#
HPB_PRST#
O
Primary Bus Reset Out (HPx_PRST#): This is asserted whenever the
primary side of the Intel® 6700PXH 64-bit PCI Hub goes through a reset,
even if hot plug is disabled. Resets the slot interface logic in hot plug serial
mode.
HPA_SIC
HPB_SIC
O
I
Serial Input Clock: This signal is normally high. It pulses low to shift
external serial input shift register data one bit position. (The shift registers
should be similar to standard “74x165” series).
HPA_SID
HPB_SID
Serial Input Data: Data shifted in from external logic on HPx_SIC.
Intel® 6700PXH 64-bit PCI Hub Datasheet
23
INTEL [ INTEL ]
