Async IRQ Source

Async IRQ Source block


Simulink® Real-Time™ Library for Asynchronous Event


The IRQ Source block configures the Simulink and Simulink Real-Time software to treat a particular Function-Call Subsystem as an Interrupt Service Routine (ISR). This block is actually a virtual block and does not exist at model execution time. However, the model initialization code sets up the CPU to execute the ISR when the specified interrupt occurs.

Block Parameters

IRQ line number

Select Auto (PCI only) to enable the Simulink Real-Time software to automatically determine the IRQ that the BIOS assigned to the board and use it.

Alternatively, select the IRQ line number you are using for this block. This depends on the characteristics of your I/O module. You may need to query the PCI bus in the target computer to find what IRQ the PCI bus assigned to your I/O module. Use the function

Valid IRQ numbers are between 3 and 15.

I/O board generating the interrupt

For many I/O boards, you need to set up the board to generate the interrupt. You might also need to set up board specific features at the beginning and/or end of an ISR. Select the board you intend to use from the drop-down list.

PCI slot (-1: autosearch) or ISA base address
  • If PCI:

    If only one board of this type is in the target computer, enter -1 to automatically locate the board.

    If two or more boards of this type are in the target computer, enter the bus number and the PCI slot number of the board associated with this driver block. Use the format [BusNumber, SlotNumber]. To determine the bus number and the PCI slot number, type:

    tg = slrt;
    getPCIInfo(tg, 'installed')
  • If ISA, enter the base address.

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