Tandy 1000 SL Technical Reference Manual page 55

Address
0 2FA
02FB
02FC
D e s c r i p t i o n
I n t e r r u p t I d e n t i f i c a t i o n R e g i s t e r
B i t
D e s c r i p t i o n
0
II
0
II
= I n t e r r u p t P e n d i n g
1-2 B i t 2
B i t 1
II
0
II It
0
II
F o u r t h L e v e l P r i o r i t y
II
0
II II
1
II
T h i r d L e v e l P r i o r i t y
I1
1
II
110
n
S e c o n d L e v e l P r i o r i t y
II 1 1 1
II
1
It
H i g h e s t L e v e l P r i o r i t y
3-7 Always L o g i c a l
L i n e C o n t r o l Register
B i t
0-1
2
3
4
5
6
7
B i t
0
1
2
3
4
5-7
D e s c r i p t i o n
B i t
1
B i t
0
It
0
II It
0
II
F i v e B i t Word L e n g t h
II
0
It II
1
II
S i x
B i t
Word L e n g t h
tI
1
It I t 0 II
S e v e n B i t Word L e n g t h
II
1
II II
1
It
E i g h t B i t Word L e n g t h
n o w
= One S t o p
B i t
II 1 1 1
=
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
"1
II
= P a r i t y E n a b l e
"0
11
= Odd P a r i t y S e l e c t
II
1
II
= Even P a r i t y S e l e c t
S t i c k P a r i t y B i t
"1" = S e t B r e a k E n a b l e
"1"
=
D i v i s o r
L a t c h
Access
B i t E n a b l e
Two S t o p B i t s W i t h S i x , S e v e n ,
o r
E i g h t
B i t
D e s c r i p t i o n
II
1
It
= Data T e r m i n a l Ready S e t (DTR)
II
0
It
= Data T e r m i n a l Ready R e s e t (DTR)
R e q u e s t To Send (RTS)
o u t 1
o u t 2
Loop
Always L o g i c a l
"0"
4 4