SAM-G53N_14 Datasheet, PDF (55/949 Pages) ATMEL Corporation – Atmel | SMART ARM-based Flash MCU

Figure 11-6. Vector Table
Exception number IRQ number Offset
Vector
255
239
IRQ239
0x03FC
.
.
.
.
.
.
.
.
.
0x004C
18
2
IRQ2
0x0048
17
1
IRQ1
0x0044
16
0
IRQ0
0x0040
15
-1
SysTick
0x003C
14
-2
PendSV
0x0038
13
Reserved
12
Reserved for Debug
11
-5
SVCall
0x002C
10
9
Reserved
8
7
6
-10
Usage fault
0x0018
5
-11
Bus fault
0x0014
4
-12
Memory management fault
0x0010
3
-13
Hard fault
0x000C
2
-14
NMI
0x0008
1
Reset
0x0004
Initial SP value
0x0000
On system reset, the vector table is fixed at address 0x00000000. Privileged software can write to the SCB_VTOR
to relocate the vector table start address to a different memory location, in the range 0x00000080 to 0x3FFFFF80,
see “Vector Table Offset Register”.
11.4.3.5 Exception Priorities
As Table 11-9 shows, all exceptions have an associated priority, with:
 A lower priority value indicating a higher priority
 Configurable priorities for all exceptions except Reset, Hard fault and NMI.
If the software does not configure any priorities, then all exceptions with a configurable priority have a priority of 0.
For information about configuring exception priorities see “System Handler Priority Registers”, and “Interrupt
Priority Registers”.
Note: Configurable priority values are in the range 0–15. This means that the Reset, Hard fault, and NMI exceptions, with
fixed negative priority values, always have higher priority than any other exception.
For example, assigning a higher priority value to IRQ[0] and a lower priority value to IRQ[1] means that IRQ[1] has
higher priority than IRQ[0]. If both IRQ[1] and IRQ[0] are asserted, IRQ[1] is processed before IRQ[0].
If multiple pending exceptions have the same priority, the pending exception with the lowest exception number
takes precedence. For example, if both IRQ[0] and IRQ[1] are pending and have the same priority, then IRQ[0] is
processed before IRQ[1].
SAM G53G / SAM G53N [DATASHEET]
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Atmel-11240E-ATARM-SAM-G53G-SAM-G53N-Datasheet_17-Oct-14