Tandy 1000 SL Technical Reference Manual page 63

Address D e s c r i p t i o n
0 3FB L i n e c o n t r o l R e g i s t e r
B i t D e s c r i p t i o n
0-1
B i t
1
B i t
0
F i v e B i t Word L e n g t h
S i x B i t Word L e n g t h
S e v e n B i t word L e n g t h
E i g h t B i t Word L e n g t h
II
0
II
11
0
I1
II
0
I1 1 1 1 I1
I I
1
II II
0
II
II
1
n
II
1
11
One S t o p B i t
2
II
0
11
=
1 3
S t o p B i t s When F i v e B i t L e n g t h S e l e c t e d
Two
S t o p B i t s W i t h S i x , S e v e n ,
or
E i g h t B i t
P a r i t y E n a b l e
3
n 1 n =
Odd P a r i t y S e l e c t
4
II
0
II
=
Even P a r i t y S e l e c t
5 S t i c k P a r i t y B i t
6 "1" = S e t B r e a k E n a b l e
7
"1" = D i v i s o r L a t c h Access
B i t E n a b l e
1 1 1 n
=
n l n
=
0 3FC
B i t
D e s c r i p t i o n
0
"11' = Data T e r m i n a l Ready S e t (DTR)
1 R e q u e s t To Send (RTS)
2 Out 1
3
o u t 2
4 LOOP
5-7 Always L o g i c a l l l O g l
1 1
0
II
= Data T e r m i n a l Ready Reset (DTR)
03FD
L i n e S t a t u s R e g i s t e r
B i t
0
1
2
3
4
5
6
7
D e s c r i p t i o n
Data Ready
( D R )
O v e r r u n E r r o r ( O R )
" 1 '
= Detect
P a r i t y E r r o r ( P E )
"1
I1
=
Detect
F r a m i n g E r r o r (FE)
II
1
I1
=
B r e a k I n t e r r u p t ( B I )
T r a n s m i t t e r H o l d i n g R e g i s t e r
II
1
I1
= C h a r a c t e r T r a n s f e r r e d From H o l d i n g To S h i f t
I1
0
II
= L o a d i n g T r a n s m i t t e r H o l d i n g R e g i s t e r
T r a n s m i t t e r S h i f t R e g i s t e r Empty
n 1 1 1
= S h i f t R e g i s t e r I d l e
n o n
= Data T r a n s f e r From H o l d i n g R e g i s t e r
Always L o g i c a l "0"
R e g
i s
t e r
5 2