SAM3X8E Atmel Corporation, SAM3X8E Datasheet - Page 77

• Manufacturer Part Number: SAM3X8E
• Manufacturer: Atmel Corporation

11.6.2.4
11.6.2.5
11.6.2.6
11.6.2.7
11.6.2.8
11.6.2.9
11.6.2.10
Table 11-9.
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
Exception
number
1
2
3
(1)
Memory management fault
Bus fault
Usage fault
SysTick
Interrupt (IRQ)
SVCall
PendSV
Properties of the different exception types
IRQ
number
1)
-
-14
-13
(
A memory management fault is an exception that occurs because of a memory protection
related fault. The MPU or the fixed memory protection constraints determines this fault, for both
instruction and data memory transactions. This fault is used to abort instruction accesses to
Execute Never (XN) memory regions, even if the MPU is disabled.
A bus fault is an exception that occurs because of a memory related fault for an instruction or
data memory transaction. This might be from an error detected on a bus in the memory system.
A usage fault is an exception that occurs because of a fault related to instruction execution. This
includes:
The following can cause a usage fault when the core is configured to report them:
A supervisor call (SVC) is an exception that is triggered by the SVC instruction. In an OS envi-
ronment, applications can use SVC instructions to access OS kernel functions and device
drivers.
PendSV is an interrupt-driven request for system-level service. In an OS environment, use
PendSV for context switching when no other exception is active.
A SysTick exception is an exception the system timer generates when it reaches zero. Software
can also generate a SysTick exception. In an OS environment, the processor can use this
exception as system tick.
A interrupt, or IRQ, is an exception signalled by a peripheral, or generated by a software
request. All interrupts are asynchronous to instruction execution. In the system, peripherals use
interrupts to communicate with the processor.
• an undefined instruction
• an illegal unaligned access
• invalid state on instruction execution
• an error on exception return.
• an unaligned address on word and halfword memory access
• division by zero.
Exception
type
Reset
NMI
Hard fault
Priority
-3, the highest
-2
-1
Vector address
or offset
0x00000004
0x00000008
0x0000000C
(2)
Activation
Asynchronous
Asynchronous
-
SAM3X/A
SAM3X/A
77
77