NVIC Register Descriptions
1626
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
Cortex-M3 Peripherals
25.5.26 Interrupt 0-133 Priority (PRI0-PRI33) Registers, offset 0x400-0x484
The Interrupt 0-133 Priority (PRI0-PRI33) registers provide 3-bit priority fields for each interrupt. These
registers are byte accessible. Each register holds four priority fields that are assigned to interrupts as
follows:
PRIn Register Bit Field
Interrupt
Bits 31:29
Interrupt [4n+3]
Bits 23:21
Interrupt [4n+2]
Bits 15:13
Interrupt [4n+1]
Bits 7:5
Interrupt [4n]
See the
Cortex-M3 Processor
chapter for interrupt assignments.
Each priority level can be split into separate group priority and subpriority fields. The PRIGROUP field in
the Application Interrupt and Reset Control (APINT) register indicates the position of the binary point that
splits the priority and subpriority fields .
Note:
This register can only be accessed from privileged mode.
Figure 25-30. Interrupt 0-133 Priority (PRI0-PRI33) Registers
31
29
28
24
23
21
20
16
INTD
Reserved
INTC
Reserved
R/W-0
R-0
R/W-0
R-0
15
13
12
8
7
5
4
0
INTB
Reserved
INTA
Reserved
R/W-0
R-0
R/W-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 25-36. Interrupt 0-133 Priority (PRI0-PRI33) Registers Field Descriptions
Bit
Field
Value
Description
31-29
INTD
Interrupt Priority for Interrupt [4n+3]
This field holds a priority value, 0-7, for the interrupt with the number [4n+3], where n is the number
of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the
priority of the corresponding interrupt.
28-24
Reserved
Reserved
23-21
INTC
Interrupt Priority for Interrupt [4n+2]
This field holds a priority value, 0-7, for the interrupt with the number [4n+2], where n is the number
of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the
priority of the corresponding interrupt.
20-16
Reserved
Reserved
15-13
INTB
Interrupt Priority for Interrupt [4n+1
This field holds a priority value, 0-7, for the interrupt with the number [4n+1], where n is the number
of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the
priority of the corresponding interrupt.
12-8
Reserved
Reserved
7-5
INTA
Interrupt Priority for Interrupt [4n]
This field holds a priority value, 0-7, for the interrupt with the number [4n], where n is the number of
the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the priority
of the corresponding interrupt.
4-0
Reserved
Reserved
25.5.27 Software Trigger Interrupt (SWTRIG) Register, offset 0xF00
The Software Trigger Interrupt (SWTRIG) Register is described below. Writing an interrupt number to the
SWTRIG register generates a Software Generated Interrupt (SGI). See the
Cortex-M3 Processor
chapter
for interrupt assignments.