PI7C8150BNDIE Pericom Semiconductor, PI7C8150BNDIE Datasheet - Page 34

• Manufacturer Part Number: PI7C8150BNDIE
• Description: IC PCI-PCI BRIDGE ASYNC 256-PBGA
• Manufacturer: Pericom Semiconductor

Specifications of PI7C8150BNDIE

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 256-PBGA
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.7.4
3.8
The PI7C8150B forwards Type 1 to Type 1 configuration write transactions as delayed
transactions. Type 1 to Type 1 configuration write transactions are limited to a single data
transfer.
SPECIAL CYCLES
The Type 1 configuration mechanism is used to generate special cycle transactions in
hierarchical PCI systems. Special cycle transactions are ignored by acting as a target and
are not forwarded across the bridge. Special cycle transactions can be generated from Type
1 configuration write transactions in either the upstream or the down-stream direction.
PI7C8150B initiates a special cycle on the target bus when a Type 1 configuration write
transaction is being detected on the initiating bus and the following conditions are met
during the address phase:
When PI7C8150B initiates the transaction on the target interface, the bus command is
changed from configuration write to special cycle. The address and data are for-warded
unchanged. Devices that use special cycles ignore the address and decode only the bus
command. The data phase contains the special cycle message. The transaction is
forwarded as a delayed transaction, but in this case the target response is not forwarded
back (because special cycles result in a master abort). Once the transaction is completed on
the target bus, through detection of the master abort condition, PI7C8150B responds with
TRDY_L to the next attempt of the con-figuration transaction from the initiator. If more
than one data transfer is requested, PI7C8150B responds with a target disconnect operation
during the first data phase.
TRANSACTION TERMINATION
This section describes how PI7C8150B returns transaction termination conditions back to
the initiator.
The initiator can terminate transactions with one of the following types of termination:
The lowest two address bits on AD[1:0] are equal to 01b.
The device number in address bits AD[15:11] is equal to 11111b.
The function number in address bits AD[10:8] is equal to 111b.
The register number in address bits AD[7:2] is equal to 000000b.
The bus number is equal to the value in the secondary bus number register in
configuration space for downstream forwarding or equal to the value in the primary
bus number register in configuration space for upstream forwarding.
The bus command on CBE_L is a configuration write command.
Page 34 of 109
ASYNCHRONOUS 2-PORT PCI-TO-PCI BRIDGE
ADVANCE INFORMATION
April 2009 – Revision 1.08
PI7C8150B