Extron electronic VTG 150 VTG 200 RS-232 Control and Connection to a Computer, Pin # Function

VTG 200 RS-232 Control and Software

VTG 200 RS-232 Control and Connection to a Computer

A computer connected to the VTG 200 RS-232 port can be used to:

•Add to the Extron supplied video scan formats in the field.

•Duplicate most VTG 200 panel operations.

Each VTG 200 ships with a 3.5” diskette containing the Extron Windows-compatible VTG 200 Control Program which enables the user to perform all of the above operations in a Windows environment. The program will be covered later in this chapter.

The VTG 200’s RS-232 port, a 9 pin D connector labeled “RS-232”, is located on the rear panel of the unit. Pin assignments and protocol are:

Pin #	Function
2	Transmit Data (Tx)
3	Receive Data (Rx)
5	Signal Ground (Gnd)

9600 baud, 8-bits, no parity, 1 start bit and 1 stop bit.

To connect the VTG 200 to a computer, refer to the picture below and connect the user supplied RS-232 cable from the computer (PC) serial port to the VTG 200 connector labeled “RS-232”.

VTG 200 RS-232 Control and Software

Host/VTG 200 Communications

The VTG 200 treats any character that it receives on the RS-232 port as a possible command, but it accepts only a limited number as legal commands. There are no codes required to say that a command is coming or that a command has ended. A simple command may be a single character typed on a keyboard and does not require any special characters before or after (it is not necessary to press “enter” from the keyboard). Simple commands could be sent from a terminal or any other controlling device.

When the VTG 200 receives a command and determines that it is valid, it will execute the command and send a response back to the controlling (host) device. If the command is determined by the VTG 200 to be invalid, an error response will be returned to the host. All responses from the VTG 200 to the host begin and end with a carriage return (CR). The second CR signals the end of the response character string (string = one or more characters).

Using the Command/Response Table

The table on the following page lists those commands which the VTG 200 recognizes as valid and the responses that will be returned to the host. The description column defines the command, the results of executing the command, or the response returned to the host.

The command string in the left column of the table is defined in the right column (both in bold print). The command string is shown as ASCII characters.

Page 5-1 Extron • VTG 150 & VTG 200 • User’s Manual Extron • VTG 150 & VTG 200 • User’s Manual Page 5-2