HCD-E1 Installation & Operation Manual Chapter 4 - Control from the Supervisory Port
11/01/00 19:23 Hardware Requirements 4-3
For multidrop operation, each HCD-E1 can be assigned a node number in
the range of 1 through 255. Assigning node number 0 to the HCD-E1 means
that it will accept and answer any message: this is not permitted in
multidrop operation. Node number 0 is however recommended for use
with both point-to-point and dial-up modes.
Each HCD-E1 can be assigned a logical name of up to eight characters. The
logical name is sent in each transmission of alarm messages. The name helps
the operator to identify the source of messages that are received by the
supervision terminal.
The relevant HCD-E1 configuration parameters are described in Section 3-5
and Section 4-5. Instructions for configuring the HCD-E1 control port appear
in Section 3-8.
Control Port
Handshaking
Protocol
The control lines being used in each DCE and DTE modes and the direction
of the control signals are detailed in the following chart.
Control Line Interface Type
DCE DTE
CTS Out Not Used
DCD Out Out
DSR Out Out
DTR In In
RI Not Used In
RTS In In
Data Terminal Ready (DTR)
The terminal sets the DTR line ON (active) to gain control over HCD-E1 and
start a configuration/monitoring session.
When the DTR is ON, the front panel controls are disabled, and the LCD
displays a message that notifies the operator that HCD-E1 is under remote
management:
• When the management mode defined by means of the DEF SP
command (or SP PARAMETERS on the front panel) is the supervision
terminal (AUXILIARY DEVICE = TERMINAL), the LCD shows TERMINAL
ON LINE.
• When the management mode is the Telnet or SNMP
(AUXILIARY DEVICE = NMS-SLIP), the LCD shows NETWORK ON LINE
and displays the IP address.
When you end the terminal control connection, returning the control to the
HCD-E1 front panel, the DTR line goes OFF (becomes inactive).