Extron electronic 68-1021-01 user manual Programmer’s Guide for the Telnet and Web Browser

Communication and Control, cont’d

Programmer’s Guide for the Telnet and Web Browser

Using the command/response table

The following are either Telnet (port 23) or Web browser (port

80)commands. There are some minor differences when you are implementing these commands via Telnet or via URL encoding using a Web browser. All commands listed below will work using either connection method but, due to some limitations of the Web browser, the encapsulation characters are modified to make sure that the Web browser will properly handle them. All examples in the command/response table show the proper implementation in a Telnet or Web browser session.

Note for Web browsers: all non-alphanumeric characters must be represented as their hex equivalent, such as %xx where xx equals the two character representation of the hex byte that needs to be sent (e.g., a comma would be represented as %2C).

Telnet	Web Browser
Escape (Hex 1B)	W [must not be encoded]
Carriage Return (Hex 0D)	Pipe Character (	)
	[must not be encoded]

When SIS commands are used through a Web browser, the URL reference is used below to shorten the examples. This would in practice be the full URL of the control interface and Web page reference including all path information.

(e.g., http://192.168.254.254/index.html)

To send any of the commands using a Web browser you need to prefix them with the full URL followed by ?cmd=. See URL Encoding later in this chapter.

With Telnet you can use either the Escape commands or

the W commands, and the carriage return or the pipe ( ) character. With the Web browser you are required to use

the W commands and the pipe character.

In either method {Data} = Data is directed to a specified port and must be encoded if non-alphanumeric.

The Command/response table for Simple Instruction Set (SIS) commands later in this chapter lists the commands that the IPL M PDP-ES interface recognizes as valid, the responses that are returned to the host, a description of the command’s function or the results of executing the command, and an

example of each command in ASCII (Telnet) and URL Encoded (Web).

Upper and lower case text can be used interchangeably except where noted.

Symbol definitions are shown below. An ASCII to HEX conversion table is also provided in figure 4-9 (below).

ASCII to HEX Conversion Table

•

Figure 4-9 — ASCII-to-HEX conversion table

Symbol definitions

= CR/LF (carriage return/line feed)

=Carriage return (no line feed)

• = Space (hard) character

X2 = Command data section

Note: For Web encoding only - Data is directed to a specified port and must be encoded (URL encoding) if non-alphanumeric. Since data can include either command terminator, they must be encoded as follows when used within the data section: space (hex: 20) would be encoded as %20 and Plus sign (hex: 2B) would be encoded as %2B.

X3 = Greenwich Mean Time (GMT) offset value (-12.0 to +14.0)

X5 = On/Off status: 0 = Off/Disable; 1 = On/Enable

X11 =Unit version number

X12 =Name is a text string up to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus sign/hyphen (-). No blank or space characters are permitted as part of a name. No distinction is made between upper- and lowercase. The first character must be an alpha character. The last character must not be a minus sign/hyphen.

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