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CHAPTER 4: Operation
4.1Front-Panel Indicators
There are a total of ten LEDs, located on the
Switch’s right front panel: nine port status LEDs
and one power LED.
Power LED:
This indicator lights when the power
is on.
Port Status LEDs:
The nine status LEDs accom-
modate the 4-Port Expansion Board as well as the
standard 5-port Switch. A port’s LED flickers
momentarily, indicating activity, whenever that port
receives data. The LED will flash only if a link is es-
tablished and actual data (not commands) is being
received.
4.2 Reset Button
Figure 1 shows the location of the reset button.
Use this button to reset the Code Operated Matrix
Switch. Any time you change the internal switch
settings, press the reset button to activate the
changes. While the Code Operated Matrix Switch
is resetting, it does not process data.
Disconnecting power from the Code Operated
Matrix Switch also resets it.
A third way to reset the switch is to use the
Remote Reset command. See
RR
in
Section 4.3.2.
4.3 ASCII Control Codes
The Code Operated Matrix Switch accepts com-
mands from any port. (No one port is designated
as a master port.) A single command consists of the
attention string, followed by a command sequence
that may be from one to three characters long. The
Help screen, shown in Fig. 2., presents all the
command sequences for the Switch.
4.3.1 T
HE
ATTENTION S
TRING
The ATTENTION string is a character string,
0 to 8 characters in length, that must precede all
commands. Enter the character string via the SET
ATTENTION command. The factory default is the
character
@
. To change the attention string, see the
A
(
Set Attention String
) command in the next section.
4.3.2 T
HE
C
OMMANDS
?
—
Help
When the Code Operated Matrix Switch receives an
ATTENTION string followed by a
?
(question mark),
it sends the HELP screen out to the port that issued the
command. See Fig. 2 on the next page.
Q
—
Query
When the Code Operated Matrix Switch receives
an ATTENTION string followed by a
Q
, it sends
the STATUS screen out to the port that issued
the command. (See Fig. 3.)
4. Operation
