at91cap7e ATMEL Corporation, at91cap7e Datasheet - Page 246

• Manufacturer Part Number: at91cap7e
• Description: Customizable Microcontroller
• Manufacturer: ATMEL Corporation

25.5.2
25.5.2.1
Figure 25-6.
25.5.2.2
Figure 25-7.
246
AT91CAP7E
Interrupt Latencies
External Interrupt Edge Triggered Source
External Interrupt Level Sensitive Source
External Interrupt Edge Triggered Source
External Interrupt Level Sensitive Source
Global interrupt latencies depend on several parameters, including:
This section addresses only the hardware resynchronizations. It gives details of the latency
times between the event on an external interrupt leading in a valid interrupt (edge or level) or the
assertion of an internal interrupt source and the assertion of the nIRQ or nFIQ line on the pro-
cessor. The resynchronization time depends on the programming of the interrupt source and on
its type (internal or external). For the standard interrupt, resynchronization times are given
assuming there is no higher priority in progress.
The PIO Controller multiplexing has no effect on the interrupt latencies of the external interrupt
sources.
• The time the software masks the interrupts.
• Occurrence, either at the processor level or at the AIC level.
• The execution time of the instruction in progress when the interrupt occurs.
• The treatment of higher priority interrupts and the resynchronization of the hardware signals.
(Negative Edge)
(Positive Edge)
IRQ or FIQ
IRQ or FIQ
nIRQ
MCK
nFIQ
(High Level)
(Low Level)
IRQ or FIQ
IRQ or FIQ
nIRQ
nFIQ
MCK
Maximum IRQ Latency = 4 Cycles
Maximum FIQ Latency = 4 Cycles
Latency = 3 Cycles
Latency = 3 cycles
Maximum IRQ
Maximum FIQ
8549A–CAP–10/08