
SCB Registers
150
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Cortex-M4 Peripherals
2.5.3 INTCTRL Register (Offset = 0xD04) [reset = 0x0]
Interrupt Control and State (INTCTRL)
NOTE:
This register can only be accessed from privileged mode.
The INCTRL register provides a set-pending bit for the NMI exception, and set-pending and clear-pending
bits for the PendSV and SysTick exceptions. In addition, bits in this register indicate the exception number
of the exception being processed, whether there are preempted active exceptions, the exception number
of the highest priority pending exception, and whether any interrupts are pending.
When writing to INCTRL, the effect is unpredictable when writing a 1 to both the PENDSV and
UNPENDSV bits, or writing a 1 to both the PENDSTSET and PENDSTCLR bits.
INTCTRL is shown in
and described in
Return to
Figure 2-15. INTCTRL Register
31
30
29
28
27
26
25
24
NMISET
RESERVED
PENDSV
UNPENDSV
PENDSTSET
PENDSTCLR
RESERVED
R/W-0x0
R-0x0
R/W-0x0
W-0x0
R/W-0x0
W-0x0
R-0x0
23
22
21
20
19
18
17
16
ISRPRE
ISRPEND
RESERVED
VECPEND
R-0x0
R-0x0
R-0x0
R-0x0
15
14
13
12
11
10
9
8
VECPEND
RETBASE
RESERVED
R-0x0
R-0x0
R-0x0
7
6
5
4
3
2
1
0
VECACT
R-0x0
Table 2-27. INTCTRL Register Field Descriptions
Bit
Field
Type
Reset
Description
31
NMISET
R/W
0x0
NMI Set Pending
Because NMI is the highest-priority exception, normally the
processor enters the NMI exception handler as soon as it registers
the setting of this bit, and clears this bit on entering the interrupt
handler. A read of this bit by the NMI exception handler returns 1
only if the NMI signal is reasserted while the processor is executing
that handler.
30-29
RESERVED
R
0x0
28
PENDSV
R/W
0x0
PendSV Set Pending
Setting this bit is the only way to set the PendSV exception state to
pending. This bit is cleared by writing a 1 to the UNPENDSV bit.
27
UNPENDSV
W
0x0
PendSV Clear Pending
This bit is write only; on a register read, its value is unknown.
26
PENDSTSET
R/W
0x0
SysTick Set Pending
This bit is cleared by writing a 1 to the PENDSTCLR bit.
25
PENDSTCLR
W
0x0
SysTick Clear Pending
This bit is write only; on a register read, its value is unknown.
24
RESERVED
R
0x0
23
ISRPRE
R
0x0
Debug Interrupt Handling
This bit is only meaningful in Debug mode and reads as zero when
the processor is not in Debug mode.