IBM Series 1 User Manual page 144

Figure 4-6.
output circuits
C
Teletypewriter adapter
¢
I
Q
Device
I
I
Top-card
connector
pin
I
AO?
SSS closed
=
data mark
0
or TTL minus
=
data mark
(SSS
=
solid state switch)
I
BO?
SSS open
=
data mark
I
0
or TTL plus
=
data mark
I
A08
I
0
SSS/TTL write control
I
B08
I
0
SSS/TTL read control
+12 V
-12 V
C
I
B06
Driver 0 EIA transmitted data
+12 V
I
-12 V
I
A06
Driver
0
EIA data terminal ready
I
+12 V
I
51 kn
5.1 kn
I
620 n
I A02
0
Current driver, current
=
mark
+12 V
I
51 kn
I
620 n
I B03
0
Current driver, current
=
space
I
(B05)
0
I
0 Logic ground
Logic ground
I
Teletypewriter Adapter
4-21