Paradyne COMSPHERE 3920Plus Technical Reference Manual page 94

COMSPHERE 392xPlus Modems
Port TXC Source: Internal
Nxt Internal External
Port Transmit Clock Source. Determines the clock source used to clock transmit data into the port buffer from Pin 2
(TXD) of the EIA-232-D interface. The port buffer is used to compensate for timing differences when a port is connected
via a crossover cable to another modem's EIA-232-D interface.
Internal – The data input to the port buffer (from Pin 2 of the EIA-232-D interface) is clocked into the buffer using the
modem's transmit clock. (The modem's transmit clock is determined by the TX Clock Source configuration option.) Data
is removed from the buffer using this same clock.
External – The data input to the port buffer (from Pin 2 of the EIA-232-D interface) is clocked into the buffer using the
clock source provided on Pin 24 (XTXC) of the EIA-232-D interface. Data is removed from the buffer using the modem's
transmit clock. (The modem's transmit clock is determined by the TX Clock Source configuration option.)
NOTE: The port buffer is re-centered each time RTS is turned ON. If there is a lack of clock synchronization, frequent
toggling of RTS will prevent the loss of data due to buffer overflow or underflow.
DTE Alarm Mask: Disable
Nxt Disable Enable
DTE Alarm Mask. Allows you to enable or disable the reporting of DTE alarms (per port) to the front panel and/or NMS.
Enable – Does not report alarms.
Disable – Reports alarms.
Extend Main Ch.: Disable
Nxt Disable Enable
Primary data can only be extended one link.
Extend Main Channel. Supports extended diagnostics. Specifies whether there is main (primary) channel connectivity
between the modem's DTE ports and the DTE ports of modems one level below (downstream) or above (upstream) in
the diagnostic network.
Enable – If this configuration option is set to Enable on a port of a tributary modem, test mode is propagated to the
modems downstream when test mode goes ON for that port.
Disable – If this configuration option is set to Disable on a port of a tributary modem, test mode is not propagated for
that port and primary channel data is clamped when in test mode.
NOTE: For an extended control modem, this configuration option is used along with the upstream port number where
the main (primary) channel is extended.
NOTE: For an extended port using V.34 modulation, only a single port rate is used for all the modem's line rates. Refer
to the Extended Point-to-Point
Upstream Port: Port1
End Port1 Port2 Port3 Port4 Port5 Port6 Port7 Port8
This configuration only appears when the Extended Main Channel is enabled.
Upstream Port. When an extended control modem's main (primary) channel is connected to a tributary modem that is
one link above it in the diagnostic network, this configuration option is set to the port number to which it is connected on
the tributary modem.
5-18
DTE Interface Configuration Options — Multiport Mode l
section in Appendix G, Sample Configurations.
Table 5-1
(9 of 9)
October 1998 3920-A2-GH30-40