311: Modem Wrap (External Modems Only); 313: Nrzi (Sdlc Only) Or Nrz Encoding; 313: Internal Or External Clocking (Bsc Only) - IBM 3270 Manual

• Operating in Data Terminal Ready/Data Set Ready (DTR/DSR) mode in
countries other than Canada.
• Connected via the CCITT V.35 Interface.
311: Modem Wrap (External Modems Only)
Enter a 1 if the modem is capable of a DTE-initiated automatic wrap test;
enter a 0 if not. (In this case, the DTE is the 3274 Control Unit. The wrap
test is initiated by the Test [DTE] control signal option via pin 18 from the
3274 Control Unit.)
If an IBM 3863, 3864, 3865, 3872, 3874, or 3875 modem is used, enter a 1 if
the Test (DTE) control signal option was activated at the time of modem
installation.
Wrap Feature: Determine whether the modem permits data to be wrapped
under control of the 3274 Control Unit or whether the modem has a switch
to control the wrap function. If the modem has the wrap capability and
wrapping can be controlled from the 3274 Control Unit, it is recommended
that this method be used.
If you are unable to determine that your modem has the wrap option
activated, enter a 0. However, note that this may require you to
recustomize at a later date if you determine later that the modem does have
\\..-!
the wrap option activated and you wish to use the wrap capability.
1
\)
~
313: NRZI (SDLC Only) or NRZ Encoding
Enter a 1 if nonreturn to zero inverted (NRZI) encoding is used; enter a 0 if
nonreturn to zero (NRZ) encoding is used. (This parameter must be
compatible with the host system communication controller and/or the
modem.)
313: Internal or External Clocking (BSC Only)
3-56
Enter a 1 if feature 6301 is installed; enter a 0 if it is not.
Note: For external modems operating at 1200 bps with 3274 feature 6301
(business machine clock) installed, you must enter 1.