Table of Contents
(continued)
Contents
Page
6
Agere Systems Inc.
Data Sheet
May 2001
and Packet Payload Engine
Ambassador T8110 PCI-Based H.100/H.110 Switch
14.2.1 Memory Architecture and Configuration ........................................................................................146
14.2.1.1 Connection Memory ..........................................................................................................146
14.2.1.1.1 Virtual Channel Switching, Nonbonded Connections ..................................147
14.2.1.1.2 Virtual Channel Switching, Bonded Connections ........................................147
14.2.1.2 Data Memory .....................................................................................................................148
14.2.1.3 Virtual Channel Memory ....................................................................................................149
14.2.2 Standard Switching ........................................................................................................................149
14.2.2.1 Constant Delay and Minimum Delay Connections ............................................................149
14.2.2.2 Pattern Mode .....................................................................................................................149
14.2.2.3 Subrate ..............................................................................................................................149
14.2.2.3.1 Subrate Switching Overview ........................................................................150
14.2.2.3.2 Subrate Switching Using T8110 ..................................................................151
14.2.2.3.3 Subrate Packing of Outgoing Bytes .............................................................152
14.2.2.3.4 Subrate Unpacking of Incoming Bytes ........................................................153
14.2.3 Virtual Channel (Packet Payload) Switching .................................................................................155
14.2.3.1 Nonbonded Channels ........................................................................................................155
14.2.3.2 Subrate ..............................................................................................................................157
14.2.3.3 Bonded Channels ..............................................................................................................158
14.2.3.4 External Buffer Access ......................................................................................................160
14.2.3.4.1 Overview ......................................................................................................160
14.2.3.4.2 Descriptor Table ..........................................................................................161
14.2.3.4.3 External Buffer .............................................................................................162
14.2.3.4.4 Transfer Protocol .........................................................................................162
14.2.3.4.5 External Buffer Data Transfer ......................................................................164
14.2.3.4.6 Descriptor Table Update ..............................................................................164
14.2.3.5 T8110 Packet Switching, Circuit Operation .......................................................................164
14.2.3.5.1 System Errors Due to Packet Switching ......................................................165
15 Electrical Characteristics .................................................................................................................................166
15.1 Absolute Maximum Ratings ...................................................................................................................166
15.1.1 Handling Precautions .....................................................................................................................166
15.2 Crystal Specifications ............................................................................................................................166
15.2.1 XTAL1 Crystal ................................................................................................................................166
15.2.2 XTAL2 Crystal ................................................................................................................................167
15.2.3 Reset Pulse ...................................................................................................................................168
15.3 Thermal Considerations for the 272 PBGA ...........................................................................................168
15.4 dc Electrical Characteristics ..................................................................................................................168
15.4.1 PCI Signals ....................................................................................................................................168
15.4.2 Electrical Drive Specifications, CT_C8 and /CT_FRAME ..............................................................168
15.4.3 All Other Pins .................................................................................................................................169
15.5 H-Bus Timing .........................................................................................................................................169
15.5.1 Timing Diagrams ............................................................................................................................169
15.6 ac Electrical Characteristics ..................................................................................................................170
15.6.1 Skew Timing, H-Bus ......................................................................................................................170
15.7 Hot-Swap ...............................................................................................................................................171
15.7.1 LPUE (Local Pull-Up Enable) ........................................................................................................171
15.8 Decoupling ............................................................................................................................................171
15.9 APLL V
DD
Filter ......................................................................................................................................171
15.10 PC Board PBGA Considerations ...........................................................................................................172
15.11 Unused Pins ..........................................................................................................................................172