Serial Communication, cont’d
SGS 408 Switcher • Serial Communication4-2
The switcher’s RS-232 connector can be connected to the serial output port of a host
device such as an ECP 1000, a computer, or a control system. This connection
makes software control of the switcher possible. Figure 4-1 shows a switcher
RS-232 connection to a host serial port connector.
Figure 4-1 — Switcher RS-232 to host connection
The RS-232 connector on the switcher is a 9-pin D female connector with the
following pin assignments:
Pin Signal Description
1 — Not used
2 Tx Transmit data
3 Rx Receive data
4 — Not used
5 Gnd Signal ground
6 — Not used
7 — Not used
8 — Not used
9 — Not used
The protocol is 9600 baud, 8-bit, 1 stop bit, no parity, and no flow control.
RS-232 Programmer’s Guide
The switcher accepts SIS (Simple Instruction Set) commands through the RS-232
port. SIS commands consist of one or more characters per command field. They do
not require any special characters to begin or end the command character sequence.
Each switcher response to an SIS command ends with a carriage return and a line
feed (CR/LF = ), which signals the end of the response character string. A string
is one or more characters.
SGS-initiated messages
When a local event such as a front panel operation occurs, the switcher responds by
sending a message to the host. The SGS-initiated messages are listed below
(underlined).
(C) Copyright 2000, Extron Electronics, SGS 408, Vx.xx
The copyright message is initiated by the switcher when it is first powered on.
Vx.xx is the firmware version number.
Reconfig
The reconfig message is initiated by the switcher when the resolution of the input
signal has changed.
The switcher does not expect a response from the host, but, for example, the host
program might request a new status.
Serial Communication
100
-
240
50/60 Hz
1.2A MAX.
R
1
G
B
H/HV
V
R
2
G
B
H/HV
V
R
3
G
B
H/HV
V
R
INPUTS
4
G
B
H/HV
V
R
5
G
B
H/HV
V
R
6
G
B
H/HV
V
R
7
G
B
H/HV
V
R
8
G
B
H/HV
V
R
PROGRAM
OUTPUTS
PROGRAM
PREVIEW
REMOTE
PROGRAM
DVI OUT
RCP
G
B
H/HV
V
R
PREVIEW
G
B
H/HV
V
RS-232
Control
PC Computer
