AT91SAM7A1-AU Atmel, AT91SAM7A1-AU Datasheet - Page 111

• Manufacturer Part Number: AT91SAM7A1-AU
• Description: IC ARM7 MCU 32BIT ROMLESS144LQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7A1-AU

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 40MHz
• Connectivity: CAN, EBI/EMI, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 49
• Program Memory Type: ROMless
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 144-LQFP
• For Use With: AT91SAM7A1-EK - BOARD EVAL FOR AT91SAM7A1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

16. Generic Interrupt Controller (GIC)
6048B–ATARM–29-Jun-06
The GIC is an 8-level priority, individually maskable, vectored interrupt controller. It can sub-
stantially reduce the software and real-time overhead in handling internal and external
interrupts.
The interrupt controller is connected to the nFIQ (fast interrupt request) and the nIRQ (stan-
dard interrupt request) inputs of an ARM7TDMI processor. See
nFIQ line can only be asserted by the external fast interrupt request input, FIQ. The nIRQ line
can be asserted by all others internal and external interrupt sources.
Figure 16-1. GIC Connection to Core
nIRQ interrupt sources. The internal interrupt sources are programmed to be level sensitive or
edge triggered. The external interrupt sources can be programmed to be positive or negative
edge triggered or high or low level sensitive.
Table 16-1.
An 8-level priority encoder allows the customer to define the priority between the different
Interrupt Source
10
11
0
1
2
3
4
5
6
7
8
9
Interrupt Sources
Internal Interrupt Source
External Interrupt IRQ0
External Interrupt FIQ
(Peripherals)
Software interrupt 3
Software interrupt 0
Software interrupt 1
Software interrupt 2
Fast interrupt
Watch Timer
Description
Watchdog
USART0
USART1
USART2
GIC
ADC0
SPI
APB
IRQ
FIQ
Figure
ARM7TDMI
AT91SAM7A1
AMBA
Bridge
Core
ASB
16-1. The processor’s
SWIRQ0
SWIRQ1
SWIRQ2
SWIRQ3
USART0
USART1
USART2
GIC Bit
ADC0
FIQ
WD
WT
SPI
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