Specifications

Installation and Operation Manual Chapter 3 Operation
FCD-E1LC Ver. 1.0 Configuration and Management Alternatives 3-5
FCD-E1LC supports two types of modems:
• Dial-up Hayes™ compatible modems. FCD-E1LC has call-in and call-out
capabilities; that is, it can accept external calls and initiate calls in order to
report alarms.
• Multidrop modems, such as the RAD SRM-8 miniature multidrop modem. The
multidrop configuration can be used to connect the supervisory ports of
several FCD-E1LC units located in close proximity to a common supervision
terminal, using multidrop modems (or digital sharing devices): these devices
enable to connect a single terminal to many FCD-E1LC units.
For multidrop operation, each FCD-E1LC unit must be assigned a node
address in the range of 1 through 255.
FCD-E1LC units also support address 0: assigning address 0 to an FCD-E1LC unit
means that it will accept and answer any message: this is not permitted in
multidrop operation. Address 0 is however recommended for use both with direct
connections, and point-to-point or dial-up modem links.
Control Port Handshaking Protocol with Supervision Terminals
The handshaking between the FCD-E1LC and the supervision terminal uses the
control lines in the CONTROL DCE supervisory port connector. Since the interface
mode is selected by software, the direction of the interface signals is the same in
both the DCE and DTE mode, and a cross-cable is required for the DTE mode.
The control lines in DCE and DTE modes and the direction of the control signals
are detailed in
Table 3-1 .
Table 3-1. Control Port Handshaking Protocol
Control
Line
Interface Type Function
DCE DTE
CTS Out Not Used Clear to Send line. The state of the CTS line is determined by
user’s configuration:
• ON – The CTS line is always ON (active).
• =RTS – The CTS line follows the RTS line.
DCD Out Out
Data Carrier Detect line. The state of the DCD line depends on the
communication address (node number):
• When the node address is 0, the DCD line is always ON (active).
• When a non-zero node address is used, the DCD line becomes ON
(active) when data is detected on the RD line, provided the
FCD-E1LC recognizes its own address in the data stream.
To simulate DTE operation, the delay between these events can be set
by the user (by means of the DCD DELAY parameter).
Note