Verilink C100 (880-502893-001) Product Manual - Manual (Page 30)

Configuration Using the DIP Switches
3-6 Verilink C100 and C150 T1/FT1 CSU/DSU 6/15/99
Density Switch pack 2 position 3 determines whether the unit will enforce
density to the Network or be Clear Channel. Position 3 in Off will
configure the unit to enforce density. This means that data from the
Channel being transmitted to the Network must meet the ones density
requirements specified in 62411 and T1.403 (approximately 1 in every 8
bits must be a one and no more than 15 consecutive zeros). If the data
from the channels violate density, the C100/C150 T-1 CSU/DSU wit
this option selected will put ones in the output data to guarantee
density compliance and in the process will put errors in the customer
data.
With position 3 On, the unit will let data from the Customer pass to the
Network transparently. If the facility provided by the T-1 Carrier is not
Clear Channel and this Clear Channel option is selected, the Customer
will experience data errors.
54016 or T1.403 Switch pack 2 position 4 selects whether the unit is compatible with
the Technical Reference 54016 or ANSI T1.403 ESF Data Link messages.
Switch pack 2 position 4 Off programs the unit to be compatible with
the 54016 specification. With this position On, the unit will be
compatible with the T1.403 specification. As with the preceding
selections, this option must match the requirements of the T-1 Carrier
provider.
Line build out Switch pack 2 positions 5 and 6 program the Line Build Out. In most
cases, this selection will be set to 0 dB which is positions 5 and 6 Off.
Timing Switch pack 2 positions 7 and 8 select the Timing option the unit will
use. Position 7 Off and 8 Off is Network supplies timing. This optio
must be selected when connecting to a public T-1 Network where data
will be going through a switch or DACS (MEGACOM, SUPERTRUNK,
etc.). With this option the C100/C150 T-1 CSU/DSU will lock its
timing on to the T-1 facility receive data and frequency lock its
transmit data to the receive data so the Network receives its own
timing back. If any of the other settings are used when connected to a
public T-1 facility, with switched services and the transmit path to the
Network is not frequency locked to the Network, timing slips will
occur. A typical indication of timing slips is frame losses occurring at a
fixed rate.