O U T
P U T C O N F I G U R A T I O N S
I X . O U T P U T C O N F I G U R A T I O N S
T w o s e t s o f j u m p e r s a r e i m p l e m e n t e d o n t h e D S - 2 0 0 0
t o c o n t r o l t h e a u x i l i a r y d r i v e r / r e c e i v e r s e t . J u m p e r s J 2
a n d J 3 p e r f o r m i d e n t i c a l f u n c t i o n s o n c h a n n e l s 1 a n d 2
respectively.
The function of J2 and J3 is to control the source
o f t h e d a t a e x c h a n g e d o n t h e a u x i l i a r y c o m m u n i c a t i o n
l i n e s . T h e o u t p u t s o u r c e s a r e r e q u e s t t o s e n d ( R T S ) ,
t r a n s m i t c l o c k ( X C L K ) , a n d t h e a u x i l i a r y i n p u t ( A U X I N ) .
T h e i n p u t s a r e c l e a r t o s e n d ( C T S ) a n d r e c e i v e c l o c k
(RCLK).
Transmission of RTS, when combined with reception of
c l e a r t o s e n d ( C T S ) , a l l o w s f o r h a n d s h a k i n g b e t w e e n t h e
1 6 5 5 0 a n d a p e r i p h e r a l d e v i c e . R T S i s t r a n s m i t t e d b y
c o n n e c t i n g p i n s 5 a n d 6 o f t h e j u m p e r b l o c k ( f i g u r e 2 1 ) .
C T S i s r e c e i v e d b y c o n n e c t i n g p i n s 1 a n d 2 ( f i g u r e 2 1 ) .
T h e R T S / C T S h a n d s h a k e c a n b e d e f e a t e d b y l o o p i n g t h e R T S
o u t p u t b a c k t o t h e C T S i n p u t . T h i s i s a c c o m p l i s h e d b y
c o n n e c t i n g p i n s 1 a n d 5 o f t h e j u m p e r b l o c k ( f i g u r e s 2 2
and 23).
R C L K i s t h e i n p u t t o t h e 1 6 5 5 0 w h i c h c o n t r o l s t h e
s h i f t r a t e f o r t h e r e c e i v e r p o r t i o n o f t h e c h i p .
G e n e r a l l y t h i s i n p u t i s p r o v i d e d b y c o n n e c t i n g i t t o t h e
X C L K o u t p u t . T h i s i s p e r f o r m e d b y c o n n e c t i n g p i n s 3 a n d
7 o f t h e j u m p e r b l o c k ( f i g u r e s 2 1 a n d 2 3 ) . R C L K m a y b e
received from an external source by connecting pins 2 and
3 (figure 22).
Transmission of XCLK can be used to help synchronize
c o m m u n i c a t i o n s w i t h a p e r i p h e r a l o r t o p r o v i d e a s h i f t
c l o c k f o r a r e c e i v e r . T r a n s m i s s i o n o f X C L K i s
a c c o m p l i s h e d b y c o n n e c t i n g p i n s 6 a n d 7 o f t h e j u m p e r
block (figure 22).
A U X I N i s t h e a u x i l i a r y i n p u t f r o m a p e r i p h e r a l
device. Connecting AUX IN to AUX OUT provides a loopback
m o d e o f o p e r a t i o n . T h a t i s , w h a t e v e r i s t r a n s m i t t e d b y
t h e p e r i p h e r a l w i l l b e f e d b a c k t o t h e p e r i p h e r a l . A U X
I N / A U X O U T l o o p b a c k i s i m p l e m e n t e d b y c o n n e c t i n g p i n s 2
and 6 of the jumper (figure 23).
iii
