Nortel Meridian 1 General Maintenance Information page 18

Page 18 of 72 Communicating with the system
Local and remote access
Options 51C, 61C, 81, and 81C terminal and modem
guidelines
553-3001-500 Standard 15.00
A terminal or a modem must remain permanently connected to an SDI port in
a network slot to provide a constant I/O interface to the system. Although
only one device can communicate with the system at a time, many devices
can be installed at local and remote locations.
When a system terminal is installed locally, it is connected directly to a serial
data interface (SDI) card, located within a module. When a system terminal
is installed at a remote location, modems (or data sets) and a telephone line
are required between the terminal and the SDI card.
If a Hayes command-set compatible (smart) modem is used at the
Meridian 1 end, you must select the dumb mode of operation,
Command Recognition OFF and Command Echo OFF, before
connecting the modem to the SDI port. Refer to the modem
instructions to set the mode of operation.
If a printer is connected to an SDI port (locally or remotely), you must disable
XON/XOFF flow control so that no characters or signals are sent to the port,
to avoid a "ping-pong" effect.
Figure 2 shows typical system terminal configurations. See "Access through
the system terminal" in Fault Clearing (553-3001-510) or Hardware
Replacement (553-3001-520) for the access procedure.
For information specific to Options 51C, 61C, 81, and 81C, see "Options
51C, 61C, 81, and 81C terminal and modem guidelines" on page 18.
Each Call Processor Card provides a data terminal equipment (DTE) port at
J21 and a data communication equipment (DCE) port at J25 on the Core and
Core/Network Module I/O panel. The designations DTE and DCE refer to the
function of the port, not the type of device that connects to the port. Therefore,
a modem (which is DCE) connects to the DTE port at J21, and a terminal
(which is DTE) connects to the DCE port at J25.
January 2002
CAUTION