2.7.2.5 Application Interrupt and Reset Control Register

The AIRCR provides priority grouping control for the exception model, endian status for data accesses, and reset control of the system. See the register summary in Table 2-44 and Table 2-49 for its attributes.

To write to this register, you must write 0x5FA to the VECTKEY field, otherwise the processor ignores the write.

The bit assignments are:

Figure 2-30. AIRCR Bit Assignments
Table 2-49. AIRCR Bit Assignments
Bits Name Type Function
[31:16] Write: VECTKEYSTAT

Read: VECTKEY

 RW Register key:

Reads as 0xFA05.

On writes, write 0x05FA to VECTKEY, otherwise the write is ignored.
[15] ENDIANNESS RO Data endianness bit:

0: Little-endian

1: Big-endian.

ENDIANNESS is set from the BIGEND configuration signal during reset.
[14:11] Reserved
[10:8] PRIGROUP R/W Interrupt priority grouping field. This field determines the split of group priority from subpriority, see 2.7.2.5.1 Binary Point.
[7:3] Reserved.
[2] SYSRESETREQ WO System reset request:

0: no system reset request

1: asserts a signal to the outer system that requests a reset.

This is intended to force a large system reset of all major components except for debug.

This bit reads as 0.
[1] VECTCLRACTIVE WO Reserved for Debug use. This bit reads as 0. When writing to the register you must write 0 to this bit, otherwise behavior is Unpredictable.
[0] VECTRESET WO Reserved for Debug use. This bit reads as 0. When writing to the register you must write 0 to this bit, otherwise behavior is Unpredictable.