Changing Interrupt Factor - Renesas M16C Series Hardware Manual

R8C/11 Group

19.2.5 Changing Interrupt Factor

The IR bit in the interrupt control register may be set to "1" (interrupt requested) when the interrupt
factor is changed. When using an interrupt, set the IR bit to "0" (interrupt not request) after changing
the interrupt factor. In addition, the changes of interrupt factors include all elements that change the
interrupt factors assigned to individual software interrupt numbers, polarities, and timing. Therefore,
when a mode change of the peripheral functions involves interrupt factors, edge polarities, and timing,
set the IR bit to "0" (interrupt not requested) after the change. Refer to each peripheral function for the
interrupts caused by the peripheral functions.
Figure 19.1 shows an Example of Procedure for Changing Interrupt Factor.
Figure 19.1 Example of Procedure for Changing Interrupt Factor
Rev.1.20 Jan 27, 2006
REJ09B0062-0120
I n t e r r u p t f a c t o r c h a n g e
D i s a b l e I n t e r r u p t
C h a n g e i n t e r r u p t f a c t o r ( i n c l u d i n g m o d e o f
p e r i p h e r a l f u n c t i o n s )
S e t I R b i t t o " 0 " ( i n t e r r u p t n o t r e q u e s t e d ) u s i n g
M O V i n s t r u c t i o n
E n a b l e i n t e r r u p t
Change completed
• I R b i t : T h e i n t e r r u p t c o n t r o l r e g i s t e r b i t o f a n i n t e r r u p t w h o s e
f a c t o r i s c h a n g e d
N O T E S :
1 . E x e c u t e t h e a b o v e s e t t i n g i n d i v i d u a l l y . D o n o t e x e c u t e t w o
o r m o r e s e t t i n g s a t o n c e ( b y o n e i n s t r u c t i o n ) .
2 . U s e t h e I f l a g f o r t h e I N T i ( i = 0 t o 3 ) i n t e r r u p t .
T o p r e v e n t i n t e r r u p t r e q u e s t s f r o m b e i n g g e n e r a t e d w h e n
u s i n g p e r i p h e r a l f u n c t i o n i n t e r r u p t s o t h e r t h a n t h e I N T i
i n t e r r u p t f a c t o r . I n t h i s c a s e , u s e t h e I f l a g w h e n a l l
m a s k a b l e i n t e r r u p t s c a n b e d i s a b l e d . W h e n a l l m a s k a b l e
i n t e r r u p t s c a n n o t b e d i s a b l e d , u s e t h e I L V L 0 t o I L V L 2 b i t s
o f t h e i n t e r r u p t w h o s e f a c t o r i s c h a n g e d .
3 . R e f e r t o " 1 9 . 2 . 6 C h a n g i n g I n t e r r u p t C o n t r o l R e g i s t e r " f o r t h e
i n s t r u c t i o n s t o b e u s e d a n d t h e i r u s a g e n o t e s .
page 188 of 204
(2 , 3 )
(3 )
(2 , 3 )
19. Usage Notes