Intel SE7221BK1-E manual 3 P64-C 66/100-MHz PCI-X Subsystem, 3.2 P64-C Arbitration

SE7221BK1-ETechnical Product Specification

and GNTx* are a special case in that they are internal to the host bridge. The following table defines the arbitration connections.

	Table 9. P32-B Arbitration Connections
Baseboard Signals		Device
PCIX REQ_N0/GNT_N0		Intel® 82541PI LAN (NIC2)

5.1.3P64-C 66/100-MHz PCI-X Subsystem

One 64-bit PCI-X bus segment is directed through the PXH. This PCI-X segment, P64-C, provides two 3.3V 64-bit PCI-X slots or one 3.3V 64-bit PCI-X riser slot, (SE7221BK1LX sku only) capable of up to 100 MHz operation (with 1 adapter, either slot is capable of 100MHz, only speeds of 66MHz are supported with two adapters populated) and supports full-length PCI and PCI-X adapters.

5.1.3.1Device IDs (IDSEL)

Each device under the PCI hub bridge has its IDSEL signal connected to one bit of AD [31:16], which acts as a chip select on the PCI bus segment in configuration cycles. This determines a unique PCI device ID value for use in configuration cycles. The following table shows the bit to which each IDSEL signal is attached for P64-C devices and corresponding device description.

		Table 10. P64-C Configuration IDs
IDSEL Value	Device
17	PCI Slot 4	(64bit/66-100MHz)/ PCI Slot 6 (64bit/100MHz) (Riser, SE7221BK1LX sku
	only)
18	PCI Slot 5	(64bit/66-100MHz)

5.1.3.2P64-C Arbitration

P64-C supports two PCI masters: two PCI-X slots or one riser slot. All PCI masters must arbitrate for PCI access using resources supplied by the ICH6. The host bridge PCI interface (ICH6) arbitration lines REQx* and GNTx* are a special case in that they are internal to the host bridge. The following table defines the arbitration connections.

	Table 11. P64-C Arbitration Connections
Baseboard Signals	Device
PCIX REQ_N0/GNT_N0	PCI Slot 4 (64bit/66M) / PCI Slot 6 (64bit/100M) (Riser, SE7221BK1LX sku
	only)
PCIX REQ_N1/GNT_N1	PCI Slot 5(64bit/66M)

16 Revision 1.3