X.21 Call Control (SBUQLS/QLB)
80-14001000-03
8–1
8
X.21 Call Control (SBUQLS/QLB)
8.1 Command format
This call control method is only available with the SBUQLS or SBUQLB.
The X.21 interface operates in circuit switched mode but it can also
handle enhanced subaddressing. This enables it to be controlled by the
DTE. Commands and indications will be encoded in the format specified
below. Any further information on the following can be obtained from the
full X.21 specification.
Commands will not be echoed back to the screen, so you will only see
the SBUQLS/QLB’s responses to the command. All commands and
indications in X.21 are in synchronous format and are preceded by at
least two sync chars.
Message format:-
<SYN><SYN><MESSAGE><+>
(Normally SYN=16
H
and
<+>=2B
H
)
The <+> at the end is only used for certain messages.
8.2 Commands
Call set-up and disconnection is performed by the interchange circuits T,
R, I, C with facilities for DTE and DCE information as specified by ITU-T.
Summary of Contents for SBUQHS/QHB
Page 92: ...Menu Diagrams 80 14001000 03 12 3...
Page 93: ...Quad User Modules User Manual 80 14001000 03 12 4 12 1 2 SBUQLS QLB Operation Menu...
Page 94: ...Menu Diagrams 80 14001000 03 12 5 12 2 SBUQHS 12 2 1 SBUQHS QHB Operation Menu...
Page 95: ...Quad User Modules User Manual 80 14001000 03 12 6 12 2 2 SBUQHS QHB Configuration Menu...
