Crosspoint Switch Module

Figure 1. Example Crosspoint Switch module.

The Crosspoint Switch module (CROSSPOINT_SWITCH) facilitates signal switching within an FPGA design. It allows you to specify any number of input and output blocks, all of which share a common signal block structure – the external input signals involved – which is definable as part of the instrument's configuration.

The interconnection between input and output blocks is completely configurable. Initial connections can be defined as part of design-time configuration, but can be changed on-the-fly at run-time, from the device's associated instrument panel. The latter enables you to switch signals without having to resynthesize and download the entire design to the FPGA.

Configuration of the instrument is carried out using the Crosspoint Switch Configuration dialog, an example of which is shown in Figure 2.

Figure 2. Configuration dialog for the Crosspoint Switch module.

Figure 3 illustrates an example of the run-time panel for this instrument, accessed by double-clicking on the icon for the instrument, in the Soft Devices chain of the Devices view.

Figure 3. Instrument panel for the Crosspoint Switch module.

Features at-a-glance

• Supports any number of input and output blocks
   
  • Customizable naming of input and output blocks
  • Defined blocks can be reordered as required

• Block structure (the external input signals) defined and shared by all I/O blocks
   
  • Customizable naming of block signals
  • Each signal can be configured to any number of bits (typically 8, 16, 32)
  • Defined signals in block can be reordered as required

• Ability to define initial interconnection of I/O blocks

• Ability to change interconnection of I/O blocks at run-time through the instrument panel

• Unconnected output blocks will retain the previous value that was output from them

Availability

The CROSSPOINT_SWITCH device can be found in the FPGA Instruments integrated library (FPGA Instruments.IntLib), located in the \Library\Fpga folder of the installation.

Designing with the CROSSPOINT_SWITCH

Use the following links to explore use of the Crosspoint Switch module in more detail: