AT91SAM7S256D-AU Atmel, AT91SAM7S256D-AU Datasheet - Page 166

• Manufacturer Part Number: AT91SAM7S256D-AU
• Description: ARM Microcontrollers - MCU 256K Flash SRAM 64K ARM based MCU
• Manufacturer: Atmel
• Series: SAM7S256r

Specifications of AT91SAM7S256D-AU

• Rohs: yes
• Core: ARM
• Processor Series: AT91SAM
• Data Bus Width: 16 bit/32 bit
• Maximum Clock Frequency: 55 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 64 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: LQFP-64
• Mounting Style: SMD/SMT
• Interface Type: 2-Wire, I2S, SPI, USART
• Length: 7 mm

23.7.2
23.7.2.1
23.7.2.2
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 processor. The resynchronization time depends on the
programming of the interrupt source and on its type (internal or external). For the standard interrupt, resynchroniza-
tion 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.
Figure 23-6.
Figure 23-7.
• 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.
Interrupt Latencies
External Interrupt Edge Triggered Source
External Interrupt Level Sensitive Source
External Interrupt Edge Triggered Source
External Interrupt Level Sensitive Source
(Negative Edge)
(Positive Edge)
(High Level)
(Low Level)
IRQ or FIQ
IRQ or FIQ
IRQ or FIQ
IRQ or FIQ
nIRQ
MCK
nFIQ
nIRQ
MCK
nFIQ
Maximum IRQ Latency = 4 Cycles
Maximum FIQ Latency = 4 Cycles
Latency = 3 Cycles
Latency = 3 cycles
Maximum IRQ
Maximum FIQ
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
166