Operator's guide
A rack-mounted DCM has a separate POWER IN connector on the back panel,
which should be attached to a 12 V DC supply. There is also a POWER OUT
connector on this panel, which allows you to daisy-chain several DCM units
together. The POWER OUT connector is provided merely for convenience: lines
from the POWER IN connector pass straight through.
An integrated DCM receives its 12 V DC power from two pins in its single
connector. See
Appendix A, “Connector pinouts”
for the positions of these pins.
2.3 Connecting to a single computer
In autonomous or temporary installations, you will only need to connect the
DCM to one computer (e.g. a laptop) for initial configuration. Follow these
instructions to make the DCM communicate with your computer.
Note that your computer must either have an RS232 (serial) port for initial
connection, or be running its own DHCP server. DHCP servers are available for
Windows, but are not supplied as standard.
If you want to connect the DCM to a local area network, follow the instructions
in
Section 2.4, “Connecting to a local network”
instead.
Connecting over a serial link
The DATA OUT port can be used to connect a DCM to a single computer
through a direct serial link. This link can be used to log in to the Linux
operating system of the DCM and transfer files. It is most useful for
maintenance and troubleshooting over a low-bandwidth connection, and for
initial setup.
To communicate over a serial link:
1. Connect an RS232 reverse serial cable between the DCM and your
computer. A suitable cable should have been supplied with the unit.
2. Run a terminal emulation program on the computer. The built-in
programs
minicom
for Linux, and
hypertrm
for Microsoft
Windows, can be used for this.
3. Configure the baud rate of the serial link. By default, the DCM uses a
baud rate of 115200, with 8 data bits, no parity bit, and one stop bit, and
without flow control.
4. Log in with your username and password, or
root
if you have not yet
created one. See
http://www.faqs.org/docs/Linux-
HOWTO/Text-Terminal-HOWTO.html
for full information on
how to set up terminal emulation under Linux.
December 2005
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