
Application Note
iii
21050 PCI-to-PCI Bridge Hardware Implementation
Contents
1.0
Introduction.........................................................................................................................5
1.1
Functional Overview..............................................................................................5
2.0
General Layout Guidelines.................................................................................................6
2.1
Pullups...................................................................................................................6
2.2
Expansion Card Routing .......................................................................................6
3.0
Clocking..............................................................................................................................7
3.1
21050 Clocking......................................................................................................7
3.2
21050 Output Clocks.............................................................................................7
3.3
Clock Implementation on the Motherboard ...........................................................8
3.4
Clock Implementation on an Option Card .............................................................8
4.0
Secondary IDSEL Mapping................................................................................................8
5.0
Data Synchronization and Interrupts................................................................................10
5.1
Using the 21050 Data Synchronization Pins.......................................................10
5.2
Controlling Write Posting.....................................................................................12
5.3
Interrupt Binding on Option Cards.......................................................................12
6.0
Arbitration.........................................................................................................................13
6.1
Primary Bus Arbitration .......................................................................................13
6.2
Secondary Bus Arbitration...................................................................................13
Support, Products, and Documentation ...........................................................................16