IBM 3164 ASCII Manual page 209

7-bit Mode Operation
F-10
The figure below shows the character set selection for the outbound operation.
01
234567
B
Sh
ift
In (SI)
SCS-GO
I
234567
234567
234567
I
Character
Character
Alternate
Special
Set 1
Characters
Graphics
Set 2
(ASCII)
SCS-G1
01
234567
B
Shift Out (SO)
The figure below shows the character set selection for the inbound/keyboard
operation.
01
234567
Character
Set 1
(ASCII)
Shift In (SI)
234567
Character
Set 2
i
SCS-G1
01 234567
234567
Alternate
Characters
B
~1!1!1l, ~
Sh;lt Out (SO)
(
(