Specifications

Watson-TDM-Manual-W.doc
Version 2.0-01
Watson TDM
Operating Manual
Revision: 2008-02-07 3-15
other errors, e.g. loss of power at NT1 or FC4. To avoid this it is possible to dis-
able Sa6-bit indication.
If the CRC4 error notification in Sa6 is enabled, Sa6=0001 indicates an E-bit re-
ceived from the NT2/TE, Sa6=0010 indicates a CRC4 error detected at the T ref-
erence point of the NT1, and Sa6=0011 indicates the simultaneous occurrence of
both errors.
If disabled, Sa6 is always 0000 in normal operation state.
As sending of Sa-bits requires regeneration of the CRC4 frames in the NT1, this
option is only activated when option 2 (Digital link with CRC processing in the
NT1) is selected.
3.4 nx64 kbit/s Interface
3.4.1 Features
• The nx64 kbit/s interface is software-configurable between V.35, V.36 and
X.21.
• The bitrate can be selected in steps of 64kbit/s from 64kbit/s (n=1) up to
9'984 Kbps (n = 156)
• Independent receive and transmit clocks for V.35 and V.36.
• Transmit clock is configurable either co-directional (clock defined by user
equipment connected to nx64 Port) or contra-directional (clock generated
from internal reference or from receiving clock).
• Detection for loss of clock and clock rate mismatch in co-directional clock
mode.
• Standard SubD25 connector (ISO 2110 for V.35, RS-530 for V.36, proprietary
for X.21) for DCE operation, other connectors (ISO 2593 for V.35, ISO 4902
for V.36, ISO 4903 for X.21) both for operation as DCE or DTE are available
by means of system cables.
• Loop 1 and Loop 2 supported, for V.35 and V.36. Loop control is also possi-
ble by circuits 140 (RL) and 141 (LL), according to V.54.
• Support for byte timing (circuit B) in X.21 mode.
• Activity indication of nx64 kbit/s interface on front LED of tabletop if operated
as DSL slave
• Multiservice operation: it is possible to use nx64 kbit/s and an E1 user inter-
faces simultaneously, sharing share the DSL bitrate between them.