Change, Tx/Rx, Baseband, Drop/Insert Menu - Paradise Datacom P300 Series Installation & Operating Handbook

description of the dialogue in this case.
Finally for data rate of 48kbps or 56 kbps, in IBS modes the Modem automatically activates the X.50
`bit stuffing` to convert to/from 64kbps (as defined for IBS operation). However in Custom IBS modes
the operator is offered the option of not using this facility. In Normal IBS modes then with 48 or 56kbps
data the satellite rate is 64kbps x 16/15, but in custom modes this can be reduced to just 48 or 56 kbps x
16/15 (or less if Minimum overhead mode is selected).

6.6.5 Change, Tx/Rx, Baseband, DROP/INSERT Menu

These screens are only shown if the Drop/Insert feature is available, standard on the P300-IBS and
above.
Drop/Insert selects the baseband mode where the Tx data is removed (dropped) from a T1 or E1 PCM
bearer, and the Rx data is placed (inserted) into a similar bearer. The modem is capable of operating in
Drop/Insert with any terrestrial interface, although in practise it is rarely used without a G.703 (DS1)
interface.
The first step is to specify to the modem which format of PCM bearer it is working with:
Change, Tx/Rx, Baseband, Drop/Insert, Bearer Menu
Following the bearer type selection, the timeslots from which the Tx data is to be Dropped (or in the Rx
case where the Rx data is to be inserted) must be specified:
Change, Tx/Rx, Baseband, Drop/Insert, Timeslot Menu
The screen above shows groups of eight timeslots selected: 1, 3, 4, 5, 17, 16, 15, 23, although any
combination is possible. The selection system works by toggling timeslots or groups of timeslots into or
out of the selection:
In mode timeslots are labelled 0 - 31. In
1 - 24.
Timeslots already in the selection are toggled out from any position of the selection when the
timeslot number is entered.
Timeslots not already in the selection are toggled on, and placed on the end of the selection.
Enter any single timeslot as a single or dual digit, eg 0, 5, 05, 23, 31
Enter groups of timeslots as two pairs eg 02-5 (two through five), 11-17, 12-2
For those familiar with other manufacturers equipment which use the term `mapping` (to relate
the terrestrial timeslot selection to the order in the satellite frame). The terrestrial timeslots are
`mapped` into the satellite frame in the order listed on this timeslot selection screen. If you want
to revise the mapping, simply re-order the timeslots on this screen. For the example shown
above the mapping would be as follows:
Terrestrial: 1
to Satellite: 1
NOTE: If the Extended D/I feature is available (standard on P300-TCM) timeslots can be arbitrarily re-
ordered, and so group selections may be down as well as up eg 11-17 means send in order
P300H P300 Series Modem Installation and Operating Handbook
Select bearer: [?]
1=G.732 2=T1-D4 3=T1-ESF
Drop TS: 1, 3-5, 17-15, 23
Toggle: ??-?? (YES) Help
3 4 5 17 16 15 23
st nd rd th th th th
2 3 4 5 6 7
and modes timeslots are labelled
th
8
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