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Hardware Interrupt

Trigger the downstream function-call subsystem from an interrupt service routine.


Create an Interrupt Service Routine (ISR) automatically in the generated code in your model. The ISR executes the downstream function-call subsystem associated with the block.

You can use this block for the following purposes:

  • Use this block to build a processor specific, an ARM Cortex-M based core, hardware interrupt block.

    You can customize the block to processor specific interrupts by providing an XML based interrupt description file. See Create Hardware Interrupt Block for an ARM Cortex-M Based Processor using an Interrupt Description File.

  • Use this block as is, in code generation to respond to the Fault and NMI interrupt service routines and trigger a downstream function-call subsystem. Make sure the FaultISR and NmiISR are available in your interrupt vector table.

Using this block, you can:

  • Create ISRs on ARM Cortex-M based processors.

  • Set ISR priority.

  • Enable or disable interrupt pre-emption.

  • Simulate the trigger of the interrupt and the downstream subsystem using a simulation input.

For hardware support packages, processor specific blocks are provided with interrupt description files. In the interrupt description file, the mask parameters are updated with interrupt groups, names, and interrupt numbers that match the processor characteristics.

This block only generates code for the specified ISR. The configuration to enable the interrupt and specific triggering options should be done in the peripheral settings.

  • Hardware Interrupt block


Interrupt group

Select an interrupt group.

Interrupt group lists all the interrupt groups from your interrupt description file. Selecting an interrupt group changes the list of values in the Interrupt name parameter.

Interrupt name

Select an interrupt service routine (ISR) to be generated.

The Interrupt name corresponds to the specific entry in the processor interrupt vector table.

Interrupt number

This read-only parameter indicates the position of the selected ISR in the interrupt vector table of your target hardware.

Simulink task priority

To set the priority of the downstream function-call subsystem, use this parameter. The default model base sample rate priority is set to 40 with a lower priority value indicating a higher priority task. These settings can be adjusted in the Solver pane of Configuration Parameter. The Simulink task priority of the selected interrupt is relative to the model base rate priority. Check the Disable interrupt pre-emption parameter to block all other interrupts while executing the selected interrupt service routine.

Disable interrupt pre-emption

By default, an interrupt can be pre-empted by a higher priority interrupt. Selecting this option allows low priority interrupts to complete their execution without being pre-empted by other interrupts.

Add simulation input port

Select this option to enable the SimIRQ block input. The interrupt block initiates a function-call in simulation when the SimIRQ input is true. However, SimIRQ is ignored in the generated code.