CHAPTER 5 INTERRUPT/EXCEPTION PROCESSING FUNCTION
User’s Manual U13850EJ6V0UD
153
5.2.3 NP flag
The NP flag is a status flag that indicates that non-maskable interrupt (NMI) servicing is under execution. This flag
is set when an NMI interrupt request has been acknowledged, and masks all interrupt requests to prohibit multiple
interrupts from being acknowledged.
After reset: 00000020H
Symbol
31
8
7
6
5
4
3
2
1
0
PSW
0
NP
EP
ID SAT CY OV
S
Z
NP
NMI servicing state
0
No NMI interrupt servicing
1
NMI interrupt currently being serviced
5.2.4 Noise eliminator of NMI pin
NMI pin noise is eliminated by the noise eliminator using analog delay. Therefore, a signal input to the NMI pin is
not detected as an edge, unless it maintains its input level for a certain period. The edge is detected after a certain
period has elapsed.
The NMI pin is used for releasing the software stop mode. In the software stop mode, the system clock is not
used for noise elimination because the internal system clock is stopped.
Содержание V850/SB1
Страница 2: ...User s Manual U13850EJ6V0UD 2 MEMO ...