Bally 5000 Plus, Руководство пользователя

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C i r cu l t
Desc r i p t i on ( co n t ' d )
V I A
U7 p i n 4 sends CSP I A1 t o t he
V I A c i r cu i t ( U 2 9 ) .
P I A
U7 p i n 5 sends CSP I A2 t o t he
P I A c i r c u I t ( U 1 9 ) .
S i mu l t a neous l y , U7 sends t he
c h i p se l e c t s i gna l t o t h e
se l e c t o r / i n t e r r u p t - I ACK4- ( U 1 0 1 ) .
Us i ng t h e se l e c t o r por t i on o f
t h e c h i p , U 1 0 1 r ecogn i z e s t h e
s i gna l . U 1 0 1 p i n 1 7 sends a
va l i d p e r i p h e r a l a d d r e s s ( VP A )
s i gna l
t o
t h e 68000
m i c r o p r ocessor ( U 1 p i n 2 1 ) . T h e
m i c r op r ocessor r ecogn i ze s t he
pa r t i cu l a r 6800 d e v i ce and
sends a v a l i d memor y a d d r e s s
( VMA ) s i gna l a t p i n 1 9 t o t h e
c h i p .
U 1 p i n 20 sends e n a b l e ( E ) c l ock
s i gna l
to t he 6800 dev i ce .
Rece i v i ng a l I 3 s i gna l s ( VMA , E ,
&
c h i p se l ec t ) , t he c h i p
( de v i ce ) i s se l ec t e d .
2 . Da t a I s t r a ns f e r r e d t h r oug h t h e
b i -d l r e c t i ona l da t a bus l i ne s
( 0* ) .
So f t wa r e a d d r e s s e s a
c h i p t h rough t he a d d r e s s l i nes
( A* ) .
3 . The m i c r o p r ocessor con t r o l s t h e
d i r e c t i on o f t h e d a t a t r an s f e r
w i t h t he r e ad/wr i t e ( R / W ) s i gna l
f r om U 1 p i n 9 t o t he c h i p .
3 . t.4PU BOARD
NOT E S
3- 1 9