Table of Contents
Advertisement
Read/Change Exception Vector
Setexec()
T h is f u n c t i o n a l l o w s y o u t o r e a d o r c h a n g e o n e o f th e 6 8 0 0 0 e x c e p t i o n v e c
to r s .
C macro format
in t v e c n u m ;
l o n g v e c a d d r , o l d a d d r ;
o l d a d d r =
S e t e x e c ( v e c n u m , v e c a d d r ) ;
Machine language format
m o v e .l
v e c a d d r , - ( s p )
m o v e . w
v e c n u m , - (s p )
m o v e . w
# 5 , - (s p )
tr a p
# 1 3
a d d q .l
# 8 , s p
Inputs
v e c a d d r
l o n g
v e c n u m
w o r d
Results
DO
o l d a d d r
l o n g
180
Setexec
T h e a d d r e s s o f th e n e w e x c e p t i o n h a n d l e r
r o u t i n e to u s e f o r th is v e c t o r . A v a l u e o f
- 1
in d i c a t e s t h a t y o u j u s t w i s h to r e a d
t h e c u r r e n t v e c t o r a d d r e s s .
T h e n u m b e r o f th e v e c t o r to r e a d o r
c h a n g e . S i n c e e a c h v e c t o r is f o u r b y t e s
l o n g , th e a d d r e s s =
T h e a d d r e s s s t o r e d in t h e v e c t o r b e f o r e t h e c a ll w a s
m a d e . T h i s a d d r e s s s h o u l d b e s a v e d , s o y o u r p r o
g r a m c a n r e s t o r e it b e f o r e t e r m i n a t i n g .
Opcode = 5
4 * v e c t o r n u m b e r
Hide quick links:
Advertisement
Table of Contents
