Extron Electronics MGP 462D - Manual (Page 50)

Software Configuration and Control
MGP 462 • Software Configuration and Control 4-2
Setting up RS-232/RS-422 Communication
The MGP 462’s RS-232/422 port is used to connect the MGP to a host or external
controlling device, such as a computer or control system, which can generate the
proper command codes and recognize the processor’s responses.
The cable used to connect the RS-232/422 port to a computer or control system
may need to be modified by removing pins or cutting wires. If unneeded pins
are connected, the processor may cease to function. See chapter 2,
Installation, for more information on wiring the
connectors.
The RS-232/422 connector on the rear panel is a 9-pin D female
connector (see the illustration at right) with the following pin
assignments.
Pin RS-232 function Description
1 – No connection
2 Tx Transmit data
3 Rx Receive data
4 – No connection
5 Gnd Signal ground
6 – No connection
7 – No connection
8 – No connection
9 – No connection
Connector pin assignments
There are several programs that enable you to connect the MGP 462 to a computer
or control device via the RS-232/422 interface, and to enter commands.
HyperTerminal for Windows is one such program that is commonly used on PCs.
For any program that you use, set up communication using the following protocol:
Baud rate: 9600
Data bits: 8
Parity: None
Stop Bits: 1
Flow Control: None
Using Simple Instruction Set (SIS™) commands
Host-to-MGP communications
The MGP 462 accepts SIS (Simple Instruction Set) commands through the
RS-232/422 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 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.
MGP-initiated messages
When a local event such as a front panel selection or an adjustment takes place, the
MGP 462 responds by sending a message to the host. No response is required
from the host. Examples of MGP-initiated messages are listed below (underlined).
(C) Copyright 2006, Extron Electronics, MGP462, Vx.xx
The MGP 462 sends the copyright message when it is first powered on. Vx.xx is
the firmware version number.
5 1
9 6
Female
Pin RS-422 function Description
1 – No connection
2 Tx- Transmit ground
3 Rx- Receive ground
4 – No connection
5 Gnd Signal ground
6 – No connection
7 Rx+ Receive data
8 Tx+ Transmit data
9 – No connection