Using simple instruction set (sistm) control, Host-to-switcher communications, Switcher-initiated messages – Extron Electronics MSW 4V SDI rs User Manual
Page 14: Error responses, Timeout, Rs-232 communication, Using simple instruction set (sis, Control, Serial communication
MSW 4V SDI rs • Serial Communication
Serial Communication
MSW 4V SDI rs • Serial Communication
3-2
3-3
Using Simple Instruction Set (SIS
TM
) Control
Host-to-switcher communications
The Extron Simple Instruction Set (SIS) commands consist of
one or more characters per field. No special characters are
required to begin or end a command character sequence. When
a command is valid, the switcher executes the command and
sends a response to the host device. All responses from the
switcher to the host end 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.
Switcher-initiated messages
When a local event, such as a front panel operation or error
condition, occurs, the switcher responds by sending a message
to the host. The switcher-initiated messages are listed below:
(c) Copyright 2006, Extron Electronics, MSW Series Switchers,
Vx.xx]
The switcher issues the copyright message and the input
selected message when it first powers on. Vx.xx is the firmware
version number.
Inn]
The switcher sends the Inn message whenever the selected
input is changed using the front panel buttons. “n” is the input
number.
Error responses
When the switcher receives a valid SIS command, it executes
the command and sends a response to the host device. If
the switcher is unable to execute the command because the
command is invalid or it contains invalid parameters, the
switcher returns an error response to the host. The error
response codes are:
E01 – Invalid input channel number (out of range)
E06 – Invalid input channel change (auto-switch active)
E10 – Invalid command
E13 – Invalid parameter
Timeout
Pauses of 10 seconds or longer between command ASCII
characters result in a timeout. The command operation is
aborted with no other indication.
RS-232 communication
Wire the RS-232 connectors as shown below.
Switcher
PC
Receiv
e
Tr
ansmit Ground
RS-232
Tx Rx
NA
DB9 Pinout (Female)
To control equipment
5
1
9
6
Pin
RS-232
Function
1
—
2
TX
Transmit data (-)
3
RX
Receive data (+)
4
—
5
Gnd
Signal ground
6
—
7
—
—
8
—
—
9
—
—
—
—
—
Figure 3-1 — RS-232 connector wiring
This port has the following RS-232 protocol:
• 9600 baud
• 1 stop bit
• No parity
• 8 data bits