Switch B7: (Except Loop Adapter Feature Machines); Machines); Switches Bl-Bs: (Loop Adapter Feature Machines Only); Machines Only) - IBM 3270 Manual

Mode
BSC SDLC
Switched (3276 only)
N/S HOX
Nonswitched, 2-wire
HOX HOX
Nonswitched, 4-wire, point-to-point
FOX FOX
Nonswitched, 4-wire, multipoint
FOX
HOX
Host modem with NEWSYNC feature
HOX
HOX
N/S
=
Not supported
Figure D-3. FDX/HDX Switch Setting Summary
Switch B7: (Except Loop Adapter Feature Machines)
This switch is not used.
Switch BS: NRZ/NRZI Switch (Except Loop Adapter Feature Machines)
The NRZ (non-return to zero)/NRZI (non-return to zero inverted) switch should be set to
define whether your modem uses NRZ or NRZI encoding when the 3276 is using SDLC
protocol; no setting is needed if the 3276 uses only BSC protocol. The switch must be
.set ON for NRZ, and OFF for NRZI.
The setting of this switch is determined by the communication line speed and the type of
modem. If the 3276 is attached to an IBM 3872 modem and SDLC is used, this switch
should be set to the NRZI (OFF) position. If the 3276 is attached to another modem, it
is recommended that you consult the modem manufacturer's representative to determine
the correct setting of this switch.
If the 3276 has an integrated modem, NRZI encoding is automatically used and the
switch setting has no effect. Neither does the switch setting have an effect when the 3276
is using BSC line control.
Figure D-6 shows how the 3276 Switch Settings Form should be filled in to set the switch
forNRZ.
Fill in the switch B8 portion of item 2 on the form.
Switches Bl - BS: (Loop Adapter Feature Machines Only)
These switch settings are ignored.
Switches B6 - BS: Line Speed Switches (Loop Adapter Feature Machines Only)
42
These three switches (labeled Bon the control panel) are set to select the primary and
secondary line speed. The selection of the primary line speed or secondary line speed is
made by setting the Primary Llne Speed/Secondary line Speed switch on the operator
panel.