MATLAB: Is it a problem if multiple boards have the same IRQ assignment in xPC Target 2.0.1 (R13SP1)

boardboardsgetxpcpciidenticalirqmultiplenumbersameSimulink Real-Timexpc

When I use the GETXPCPCI command, I notice that several of the boards have the same IRQ assignment.

Best Answer

The IRQ assignment only matters if the board requires an interrupt request, and most boards do not require them. The xPC Target kernel sets the Ethernet board up to use interrupts, but not the graphics board. Therefore, it does not matter if the graphics board has the same IRQ assignment as any other board.
The boards that require an interrupt request are listed below:
1) Computer Boards (Measurement Computing) PCI-CTR05, but only if you are using the external input to generate an interrupt.
2) BittWare Audio PMC always, because the driver requires an interrupt.
3) United Electronic Industries boards, but only in frame mode. In non-frame mode, the IRQ does not matter.
4) Diamond Systems MM-32 in frame mode.
5) Quatech serial port boards.
6) Diamond Emerald MM and MM-8 serial port boards.
This restriction comes from the fact that the xPC Target kernel only allows a single interrupt routine per IRQ. Only the last board registered is executed if multiple boards share the same IRQ line number.
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