Interrupt Management
[Nut/OS API]

Collaboration diagram for Interrupt Management:

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Detailed Description

Interrupt support.

Note, that it is not required to register interrupts with Nut/OS. Actually, this will route interrupts through the kernel, which results in performance degradation.

If fast interrupt processing is required, drivers as well as applications should consider using native interrupt handlers. Your compiler documentation is the right source to check how this can be done.

Functions
void	CallHandler (IRQ_HANDLER *irh)
	Call a registered interrupt handler.
int	NutRegisterIrqHandler (IRQ_HANDLER *irq, void(*handler)(void *), void *arg)
	Register an interrupt handler.
int	NutIrqEnable (IRQ_HANDLER *irq)
	Enable a specified interrupt.
int	NutIrqDisable (IRQ_HANDLER *irq)
	Disable a specified interrupt.
int	NutIrqSetPriority (IRQ_HANDLER *irq, int level)
	Modify the priority level of an interrupt.
int	NutIrqSetMode (IRQ_HANDLER *irq, int mode)
	Modify the interrupt mode.

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Function Documentation

int NutRegisterIrqHandler (  IRQ_HANDLER *  irq, void(*)(void *)  handler, void *  arg )

Register an interrupt handler. This function is typically called by device drivers, but applications may also implement their local interrupt handlers. Parameters: irq  Interrupt to be associated with this handler. handler  This routine will be called by Nut/OS, when the specified interrupt occurs. arg  Argument to be passed to the interrupt handler. Returns: 0 on success, -1 otherwise.

int NutIrqEnable (  IRQ_HANDLER *  irq  )

Enable a specified interrupt. Parameters: irq  Interrupt to enable. Returns: 0 on success, -1 otherwise.

int NutIrqDisable (  IRQ_HANDLER *  irq  )

Disable a specified interrupt. Parameters: irq  Interrupt to disable. Returns: 0 on success, -1 otherwise.

int NutIrqSetPriority (  IRQ_HANDLER *  irq, int  level )

Modify the priority level of an interrupt. The function returns the old priority, which makes it easy to temporarily switch to another priority and later set back the old one. Note: Not all targets support dynamic interrupt prioritization. Check the hardware data sheet for valid levels. Parameters: irq  Interrupt to modify. level  New priority level. Returns: Old priority level or -1 in case of an error.

int NutIrqSetMode (  IRQ_HANDLER *  irq, int  mode )

Modify the interrupt mode. The function returns the old mode, which makes it easy to temporarily switch to another mode and later set back the old one. Note: Not all targets support all modes. Check the hardware data sheet for valid levels. Parameters: irq  Interrupt to modify. mode  New priority level. Returns: Old mode or -1 in case of an error.

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