Comtech EF Data CDM-600/600L - Manual (Page 162)

CDM-600/600L Open Network Satellite Modem Revision 3
Clocking Modes and Drop and Insert (D&I) MN/CDM600L.IOM
8–8
8.7 Time Slot Selection
Selection of the transmit and receive data rates may be made in certain 64 kbps increments and
may be independent of each other. The actual satellite rates for Open Network D&I are 16/15 of
the transmit or receive data rate to include IBS overhead per IESS
- 309, although this is
transparent to the user. For E1, the user can select any time slot (TS) from 1 to 31.
Selection of TS 0 is not permitted.
For T1, the user can select any time slot (TS) from 1 to 24. The user may also select “N/A” to
leave a satellite channel unused.
The configuration menu allows time slots to be selected for transmission or reception up to the
maximum dictated by the selected transmit or receive data rate, and may be selected in arbitrary
order. As an example, if the data rate is set to 256 kbps, the maximum number of time slots that
can be dropped or inserted is 4 (being 4 x 64 kbps).
Note that, for 1920 kbps data rate the timeslots may not be manipulated. This is the ‘fixed
channel’ mode where Timeslot 1 is assigned to Channel 1, and so on.
For D&I++ framing, all increments of 64 kbps are allowed up to a maximum of 24 (1536 kbps).
For this mode, the satellite rate is 46/45 of the front panel data rate (2.22%).