Tandy 1000 SL Technical Reference Manual page 96

PIN
NAME
HLDA
INTAB
QTY.
1
1
OSCIN 1
M A 0
-
M A 8 9
WEHB, WELB 2
RASOB
,
RASlB 4
RAS2B ,RAS3B
CASB 1
DRQ1, DRQ3 3
FDDMARQ
DACK1, DACK3 3
FDDMACKB
DMATC
1
ROMCS OB 2
ROMCSlB
-
I / O DESCRIPTION
O u t p u t I n d i c a t e s
DMA
c y c l e i n
p r o g r e s s .
O u t p u t Decode of
S 2
-
S O t o
i n d i c a t e a n i n t e r r u p t
a c k n o w l e d g e c y c l e i n
p r o g r e s s .
I n p u t
C l o c k i n p u t , 30 MHz max,
5 0
%
d u t y c y c l e .
O u t p u t s M u l t i p l e x e d Memory
A d d r e s s e s . I n t e n d e d t o
d r i v e 20 M O S memory
d e v i c e s .
O u t p u t s Memory
w r i t e
e n a b l e
s i g n a l , a c t i v e l o w .
I n t e n d e d t o d r i v e 1 0 M O S
memory d e v i c e s .
O u t p u t s Memory Row A d d r e s s
S t r o b e s , a c t i v e low.
I n t e n d e d t o d r i v e 1 6
MOS
memory d e v i c e s .
A l l
o t h e r s i n t e n d e d t o d r i v e
4 MOS memory d e v i c e s
e a c h .
O u t p u t Memory Column A d d r e s s
S t r o b e s , a c t i v e low.
Each i n t e n d e d t o
d r i v e 20 M O S memory
d e v i c e s .
I n p u t s DMA c h a n n e l r e q u e s t s .
O u t p u t s
DMA
a c k n o w l e d g e s i g n a l s .
O u t p u t DMA e n d
of p r o c e s s
s i g n a l .
O u t p u t A c t i v e Low ROM C h i p
s e l e c t
v a l i d d u r i n g
a
MEMR
w i t h A17,
A l a ,
and
A 1 9 a c t i v e .
3