Interrupt Management

Interrupt support. More...

Collaboration diagram for Interrupt Management:

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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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.

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Function Documentation

void CallHandler

(

IRQ_HANDLER *

irh

)

Call a registered interrupt handler.

References IRQ_HANDLER::ir_arg, and IRQ_HANDLER::ir_handler.

Referenced by IrqHandler().

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.

References IRQ_HANDLER::ir_arg, IRQ_HANDLER::ir_ctl, IRQ_HANDLER::ir_handler, NULL, NUT_IRQCTL_INIT, and rc.

Referenced by AceInit(), ADCInit(), AhdlcAt91Init(), AhdlcAvrInit(), At91Spi0Init(), At91SpiBusNodeInit(), AtCanInit(), Avr32Spi0Init(), Avr32SpiBusNodeInit(), AvrSpiBus0NodeInit(), DmInit(), EmacInit(), FeederThread(), GpioRegisterIrqHandler(), IDEInit(), LancInit(), Lpc177x_8x_MciInit(), Lpc17xxEmacInit(), NicInit(), NplRegisterIrqHandler(), NutRegisterCanBus(), NutRegisterTimer(), NutRegisterTwiBus(), Sc16is752UsartDeinit(), Sc16is752UsartInit(), SJAInit(), UartAvrInit(), VsPlayerInit(), and wlandrv_Init().

int NutIrqEnable

(

IRQ_HANDLER *

irq

)

Enable a specified interrupt.

Parameters:

irq	Interrupt to enable.

Returns:

0 on success, -1 otherwise.

References IRQ_HANDLER::ir_ctl, NULL, NUT_IRQCTL_ENABLE, and rc.

Referenced by ADCInit(), AhdlcAt91Open(), At91Spi0Init(), At91SpiBusNodeInit(), Avr32Spi0Init(), Avr32SpiBusNodeInit(), EmacRxThread(), FeederThread(), GenCharSize(), GpioRegisterIrqHandler(), Lpc177x_8x_MciInit(), Lpc17xxEmacRxThread(), NicRxLanc(), NplRegisterIrqHandler(), NutRegisterCanBus(), NutRegisterTimer(), NutRegisterTwiBus(), Sc16is752UsartInit(), and VsPlayerInterrupts().

int NutIrqDisable

(

IRQ_HANDLER *

irq

)

Disable a specified interrupt.

Parameters:

irq	Interrupt to disable.

Returns:

0 on success, -1 otherwise.

References IRQ_HANDLER::ir_ctl, NULL, NUT_IRQCTL_DISABLE, and rc.

Referenced by GenCharSize(), NutDestroyTwiBus(), and VsPlayerInterrupts().

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.

References IRQ_HANDLER::ir_ctl, NUT_IRQCTL_GETPRIO, NUT_IRQCTL_SETPRIO, and rc.

Referenced by NutRegisterCanBus(), NutRegisterTimer(), and NutRegisterTwiBus().

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 interrupt mode: NUT_IRQMODE_NONE No change. Used to query current mode. NUT_IRQMODE_LOWLEVEL Low level sensitive. NUT_IRQMODE_HIGHLEVEL High level sensitive. NUT_IRQMODE_FALLINGEDGE Negative edge triggered. NUT_IRQMODE_RISINGEDGE Positive edge triggered. NUT_IRQMODE_EDGE Triggers on any edge or active internal edge. NUT_IRQMODE_LEVEL Triggers on level change or active internal level.

Returns:

Old mode or -1 in case of an error.

References IRQ_HANDLER::ir_ctl, NUT_IRQCTL_GETMODE, NUT_IRQCTL_SETMODE, NUT_IRQMODE_NONE, and rc.

Referenced by FeederThread(), NicRxLanc(), NplRegisterIrqHandler(), NutRegisterTwiBus(), Sc16is752UsartInit(), and VsPlayerInit().