AN 294: Crosspoint Switch Matrices in Altera MAX Series

ID 683806
Date 9/22/2014
Public Configuration

The process of switch configuration is exactly the same as a 16 × 16 crosspoint switch. You can add a register to LOAD REGISTERS and CONFIGURATION REGISTERS to store the tri-sate bit. This results in a total of three bits for a 4-port customized crosspoint switch: two bits for an input address and one bit for a tri-state. The two most significant bits (MSBs) in each register identify the input that connects to that output, and the least significant bit (LSB) controls whether the output is active or tri-state.

Reset mode for this customized design is different from the 16 × 16 crosspoint switch because all ports are bidirectional. When in reset mode, all the bidirectional ports are in an initialized state and all the ports are in tri-state mode.