P300H
P300 Modem Installation and Operating Handbook
Page 57
Dropped TS: [?]
1=Leave 2=Replace with idle code
Change, Tx/Rx, Baseband, Drop/Insert, Idle Menu
G.732 Chan Assoc Sig in TS16: [?]
1=Normal (ignore) 2=Transfer via sat o/h
Change, Tx/Rx, Baseband, Drop/Insert, CAS Menu
The Modem hardware is capable of duplication and omission of timeslots, although the operator interface
(described above) does not allow such selections. If this is a requirement, please contact the factory to
discuss your needs.
After the timeslot selection the following prompt appears:
When data is `Dropped` from the bearer, there is the option to either leave the Tx data on the bearer, or
to replace it with an idle code. If the Rx data is to be inserted into the same timeslots as the as the Tx data
has been dropped from, then the Rx data will replace the Tx and it is of no consequence if it is first replaced
by Idle code or not.
LEAVE
The Tx data remains on the bearer, and will be accessible to downstream
equipment (unless Rx data inserted over it)
REPLACE
The Tx data is replaced as follows [MSB..LSB]:
G.732 Timeslots:
[01010101]
G.732 CAS in TS16:
[0101] (if CAS signalling mode active)
T1-ESF & T1-D4 Timeslots:
[10000000]
Note that in G.732 mode, TS0 is never replaced with idle code even if it is part of the Drop selection and
Idle is selected.
If the modem is set for
CLOSED NETWORK
or standard
IDR
operation the dialogue finishes here.
If the modem is set for
CUSTOM IDR
(Low rate format) then skip to the
T
on page 60
If the Extended D/I feature is available (Standard on P300-TCM) and is set for
Closed Net Plus ESC
,
IBS
or
CUSTOM IBS
, then the following two prompts appear depending on the PCM bearer selected. Note that
Channel Associated Signalling (CAS) & Robbed Bit Signalling (RBS) are described in para 10.2 "Signalling
Systems Introduction: CCS, CAS & RBS" on page 198 if required.
For
G.732
bearer operation (with the Extended D/I feature available):
NORMAL
(IGNORE)
TS16 does not contain CAS (ie a terrestrial CAS multiframe and `abcd` signalling
nibbles for each timeslot). It is simply treated as a normal data timeslot and may
be dropped / inserted as with any other timeslot.
TRANSFER
TS16 contains CAS and by implication a terrestrial multiframe in order to carry the
CAS. If selected, the terrestrial multiframe will be acquired, and CAS removed
from/replaced into the Drop/Insert bearer. The CAS will be conveyed
transparently from end to end of the link within IBS (or custom IBS) overheads.