Tandy 1000 SL Technical Reference Manual page 51

Address D e s c r i p t i o n
OOC4-OOC7
DAC
F u n c t i o n s
OOC4
write
B i t s 0-1
0 OC4
B i t 0
0
0
1
1
B i t 2
0
1
B i t
3
0
1
B i t
4
0
1
B i t
5
0
1
B i t 6
0
1
B i t 7
R e a d
B i t 3
B i t
7
B i t
1
DAC
F u n c t i o n S e l e c t e d
0 J o y s t i c k
1
S u c c e s s i v e A p p r o x i m a t i o n
0
s o u n d C h a n n e l
1 Direct W r i t e t o
DAC
DMA E n a b l e ( f o r SA,
Direct
R/W)
DMA
D i s a b l e d
DMA
E n a b l e d f o r SA,
DA
DMA I n t e r r u p t Clear
DMA I n t e r r u p t Held Clear
DMA I n t e r r u p t Allowed
DMA
I n t e r r u p t E n a b l e
DMA
EOP I n t e r r u p t D i s a b l e d
DMA
EOP I n t e r r u p t E n a b l e d
Sound D i v i d e r S y n c E n a b l e
S y n c h r o n i z a t i o n D i s a b l e d
Sync E n a b l e d
( W r i t e t o OOC6
o r
OOC7 r e l o a d s
a l l d i v i d e r s )
Sound C h i p
E x t r a
D i v i d e E n a b l e
E x t r a D i v i d e D i s a b l e d
E x t r a D i v i d e E n a b l e d
R e s e r v e d
DMA
I n t e r r u p t F l a g . A
DMA
I n t e r r u p t h a s
o c c u r r e d . To
clear
t h e i n t e r r u p t f l a g , B i t 3
m u s t b e b r o u g h t
l o w
a n d t h e n h i g h a g a i n .
S u c c e s s i v e A p p r o x i m a t i o n Done. U s e f u l when
p o l l i n g i n s t e a d
of
u s i n g DMA.
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