7 interrupt flag register (ifr) – Texas Instruments TMS320C67X/C67X+ DSP User Manual
Page 44

Control Register File
CPU Data Paths and Control
2-18
SPRU733
2.7.7 Interrupt Flag Register (IFR)
The interrupt flag register (IFR) contains the status of INT4−INT15 and NMI
interrupt. Each corresponding bit in the IFR is set to 1 when that interrupt
occurs; otherwise, the bits are cleared to 0. If you want to check the status of
interrupts, use the MVC instruction to read the IFR. (See the MVC instruction
description, page 3-180, for information on how to use this instruction.) The
IFR is shown in Figure 2−8 and described in Table 2−10.
Figure 2−8. Interrupt Flag Register (IFR)
31
16
Reserved
R-0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
IF15 IF14 IF13 IF12 IF11 IF10
IF9
IF8
IF7
IF6
IF5
IF4
Reserved
NMIF
0
R-0
R-0
R-0
R-0
Legend: R = Readable by the MVC instruction; -n = value after reset
Table 2−10. Interrupt Flag Register (IFR) Field Descriptions
Bit
Field
Value Description
31−16 Reserved
0
Reserved. The reserved bit location is always read as 0. A value written to this
field has no effect.
15−4
IFn
Interrupt flag. Indicates the status of the corresponding maskable interrupt. An
interrupt flag may be manually set by setting the corresponding bit (ISn) in the
interrupt set register (ISR) or manually cleared by setting the corresponding bit
(ICn) in the interrupt clear register (ICR).
0
Interrupt has not occurred.
1
Interrupt has occurred.
3−2
Reserved
0
Reserved. The reserved bit location is always read as 0. A value written to this
field has no effect.
1
NMIF
Nonmaskable interrupt flag.
0
Interrupt has not occurred.
1
Interrupt has occurred.
0
0
0
Reset interrupt flag.