Quartus® Prime Pro Edition User Guide: Platform Designer

ID 683609
Date 4/17/2025
Public
Document Table of Contents

6.12.6.4. Routing Mechanism—16x16 Crossbar Example

The following describes the routing mechanism for a 16x16 crossbar example system:

Example System Description

  • Example System: 16x16 Crossbar
  • TDEST width: 4 bits.
  • TID width: 2 bits.
  • Channel width:
    <TID_width> + <TDEST_width> = 2 + 4 = 6 ()

Fundamental block: 4x4 Avalon Streaming crossbar

The fundamental example block comprises the following components:

  • 1:4 Avalon Streaming Demultiplexer:
    • Channel width of 6.
    • 2 higher order bits for routing.
    • 4 lower order bits passed on.
  • 4:1 Avalon Streaming Multiplexer
    • Channel width 6.
    • 4 higher order bits of mux output channel pass on channel input.
    • 2 lower order bits indicate mux input#.

Example Source and Destination

  • Source: Transmitter#15 (1111)
  • Destination: Receiver#7 (0111)
  • TID: 01  

Routing at hop1

  • Channel input to demux3: {TDEST_TID}: 0111_01
  • Channel output of demux3: 1101
  • Channel input to mux1: 1101
  • Channel output of mux1: 1101_11

Routing at hop2

  • Channel input to demux3: 1101_11
  • Channel output of demux3: 0111
  • Channel input to mux3: 0111
  • Channel output of mux3: 011111 => {TID, TDEST} => {01, 1111 
Figure 296. Overall Routing Representation from Example


Figure 297. hop1 Routing in 4x4 Crossbar


Figure 298. hop2 Routing in 4x4 Crossbar