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M o d e l 5363 8
S e r v i c e
8- 1 1 1 .
E X E C U T E C O M M A N D A N D GO TO .
G O T O ro u t i n e at a d d ress 2 5 2 o c t 3 7 4 . R O M
m o d e . T h e l o w f ro m
a b i n a ry ad d ress 1 00 1
c o m m a n d L D STO P . T h e l o w f ro m
A n o t h e r h i g h i s a p p l i e d to U 2 2 A p i n 1 f ro m R O M
en a b l i n g t h e L O A D i n p u ts t o state c o u n te rs U 2 5 a n d U 2 8 . T h e n e xt c l o c k p u l se w i l l i n i ta t e
co m m a n d L D STO P a n d c l o c k i n p a ra l l e l data o n U 2 5 a n d U 2 8 p i n s 3 t h ro u g h 6 . T h u s t h e state
c o u n t e rs w i l l j u m p f r o m a d d ress 2 5 2 oct 374 to 29 oct 35, b i n a ry 0 0 0 1 1 1 0 1
8-1 1 2 .
E X A M I N E Q U A L I F I E R/J U M P I F 1 . An e xa m p l e o f e xa m i n e q u a l i f i e r/j u m p i f 1 i s s h o w n
Figure 8 - 6 .
i n
T h e d i a m o n d s h a ped b o x at a d d re ss 44 o c t 54 i s a q ua l i f i e r d ec i s i o n b o x . T h e
d e pe n d e n t q u a l i f i e r l i n e to be e xa m i n e d i s i n d i c a ted b y t h e C w i t h i n t h e b o x . At R O M a d d re ss
44 , oc t 54 R O M o u t p u t
m o d e . I n t h i s c o n d i t i o n , n e i t h e r t h e c o m m a n d d e c o d e r or l a t c h a re e n a b le d , a n d q u a l i f i e r f l i p
f l o p U 2 3 A i s n o t preset, a n d t h e refore f ree to s t o re a q ua l i f i e r. T h e l o w o n R O M o u t p u t 0 8
e n a b l e s q u a l i f i e r d e c o d e r U 2 1 , wh i l e o u t p u ts
i n p u t 1 1 w h i c h i s t h e C data l i n e . T h e state o f t h e C d a ta l i n e w i l l b e fed t h ro u g h U 2 1 a n d U 2 2 D ,
t h e n l a t c h e d a n d store i n U 2 3 A o n t h e n e xt c l o c k p u l se . T h e h i g h o n R O M o u t p u t
prog r a m s U 2 2 A f o r a h i g h q u a l i f i e r j u m p . T h a t i s , t h e h i g h f r o m
q u a l if i e r b it f r o m U 2 3 A w i l l d ri ve U 2 2 A p i n 3 l o w , e n a b l i n g t h e L O A D i n p u t s t o j u m p state
c o u n t e rs U 25 and U 2 8 . C o n ve rse l y , a low q u a l i f i e r b i t f ro m U 23A w o u l d force U 2 2 A p i n 3 h i g h ,
a l l o w i n g t h e state c o u n t e rs t o i n c re m e n t o n e a d d re ss. I f data l i n e C i s h i g h , t h e state c o u nte rs
w i l l j u m p to t h e a d d ress o n t h e i r i n p u t s , p i n s 3 t h ro u g h 6 , 00 1 1 1 1 0 1 , d ec i m a I 6 1 , o c t 75 . I f d ata
l i n e C i s low, t h e state c o u n te rs w i l l i n c re m e n t f ro m ad d re ss 44 , o c t 54 , to a d d re ss 4 5 oct 5 5 , .
T h u s t h e state m a c h i n e w i I I select a q u a l i fi e r b i t , d e t e r m i n e i f i t i s a H i g h , a n d i f i t i s , j u m p t o a n
i n d i c a ted ad d re s s .
8- 1 1 3 .
Add resse s 62 oct 76 a n d 46 o c t 56 a re a l so e xa m i n e q u a l i f i e r state s , a n d o p e rate a s
d e s c r i bed p revi o u s l y . H o w e v e r , t h e q u a l i f i e r l i n e i n d i c ated i s G N D , refe rri n g t o e i t h e r U 1 5 1 0 o r
U 2 1 1 6. Si n c e t h e se l i n e s a re p e rm a n e n t l y g ro u n d e d , t h e path c h o sen w i l l b e f i xed . T h ese
q u a l i f i e rs a re u sed f re q u e n t l y t h ro u g h o ut the f l o wc h a rts f o r a forced J u m p , a s in state 62 . oct
7 6 or d u m m y state a s in state 46 ' oc t 56 .
8-26
0 1 5
e n a b l e s c o m m a n d d e c od e r U 1 1 . R O M o u t p u ts
9 d e c i m a l t o U 1 1 p i n s 2 0 t h ro u g h 2 3 . T h i s s e l e c t s U 1 1 o u t p u t 9 o r
0 1 5
a l s o p r e sets U 2 3 A . a p p l y i n g a h i g h to U 2 2 A p i n 2 .
0 1 5
0 1 4
a n d
a re b o t h 1 , sett i n g t h e e xa m i n e q u a l i f i e r a n d j u m p i f Q = 1
Fig u re 8-5
a l so s h o ws a n e xec ute c o m m a nd a n d
0 1 5
0 1 4
i s a 0 a n d
i s a 1 sett i n g t h e c o m m a n d
0 1 0
0 1 4 .
T h i s d ri ve s U 22 A o u t p u t p i n 3 l o w ,
0 1 0
0 1 2
t h r o u g h
s e l e c t a d d ress 0 0 1 , q ua l i f i e r
0 1 4
c o m b i n ed w i t h a h i g h
0 1 3
t h ro u g h
a p p l y
0 1 4
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