2-wire full-duplex IDSL modem with remote management extends data
transmission to 7.0 km (4.3 miles)
ASMi-31 is a 2-wire full-duplex
IDSL modem with remote management that extends data transmission to
7.0 km (4.3 miles) irrespective of data rate. ASMi-31 operates
synchronously or asynchronously at user-selectable data rates from
1.2 to 128 kbps.
The modem uses 2B1Q line code and adaptive equalizers to provide
immunity from background noise, eliminate normal
line distortion, and enable efficient transmission over 2-wire
twisted pair cables.
ASMi-31 is available as a “master” or “slave” standalone unit. The
master modem includes a front panel LCD and control buttons. The
slave modem has a blank front panel with a special 20-pin connector
for a portable control unit (PCU) connection.
The master modem provides
full-duplex inband management of the remote unit. Management data is
transmitted over the
D-channel to ensure simultaneous configuration of the local and
remote units, activation of real-time alerts on system faults, and
initiation of diagnostic tests.
ASMi-31 supports a wide range of digital interfaces: V.24/RS-232,
V.35, X.21, RS-530, V.36/RS-449 and G.703 Codirectional (64 kbps).
In addition, the modem supports a built-in Ethernet bridge (IR-ETH)
and IP router (IR-IP) to allow
LAN-to-LAN connectivity using IDSL technology. ASMi-31 can be
managed via the front panel buttons and LCD (in the master unit).
The ASMi-31 clock source depends on the modem's functional mode
(master or slave):
• Master clock: INT derived from internal oscillator or EXT derived
from the DTE interface
• Slave clock: RCV (recovered from line signal).
The user-selectable carrier may be continuous or controlled by RTS
for passing control signals end-to-end. ASMi-31 has wide diagnostic
capabilities that include the following test options:
• V.54 local analog and remote digital loopbacks
• BER testing per V.52. Line interface circuitry protects against
lightning and power surges.