Query string, Code examples | Extron electronic SFI244 Series

Communication and Control, cont’d

Server Side Include Using a Remote SIS command

		SIS Command
<!--#echo var=" W 1	* 5	* 3 *	3L	RS	Hello	"-->



Delimiter					Delimiter
Port	Time to wait	Time between	Length or	Command	Data to be passed to
Number	for first character	characters	Delimiter		external device
	of response	in response	parameter		via a serial port
					via a serial port

SIS Command

Elements

*type with no spaces

Figure 4-23 — Example of SSI “remote” command

In figure 4-23 above, a “remote” serial command sends the word “hello” and will wait up to 50ms for a response (until three characters are received). For more information on this command, refer to the Command/response table for Simple Instruction Set (SIS) commands earlier in this chapter.

Query string

A query string is the portion of a URL that appears after the question mark. The query string contains parameters or instructions for the Web server to execute.

The basic format for a query string within a link is:

<a href=”index.html?cmd=x”>Input #1</a> Where x is the SIS command to be executed.

When a link is accessed on a Web page, the URL is passed to the Web server to tell it which Web page to return to the browser. The portion of the URL after the question mark is the query string, which contains the SIS command that the IP Link product will remove and execute.

As with SSI formatted commands, query strings can use any valid SIS command—either “host” or “remote”.

The query string in figure 4-24 below will turn off DHCP on the IP Link device.

URL with a Query String using a Host SIS command

			SIS Command
<a href="index.html ?		cmd=	W0DH	">	DHCP off </a>
	Starts
HTML code	Query String	Tells web server	SIS command	HTML code	Linked Text	Closes
for a link		the an SIS follows	to be processed	for a link		Link
			by the IP Link

*type with no spaces

Figure 4-24 — Example of a host query string command

4-30 IPL T SF24 and IPL T SFI244 • Communication and Control

URL with a Query String using a Remote SIS command

				SIS Command
<a href="index.html ?		cmd=	W 2				">	Input #1	</a>
				RS		1!


	Starts		Delimiter		Delimiter
HTML code	Query String	Tells web server	Port	Command		Data to be passed to	HTML code	Linked Text	Closes
for a link		the an SIS follows	Number			Data to be passed to	for a link		Link
for a link		the an SIS follows	Number			external device	for a link		Link
						external device
						via a serial port
								*type with no spaces

	Figure 4-25 — Example of a remote query string
	command
	In figure 4-25 above, the data string that follows the pipe (								)



	symbol will be sent to the attached controlled device on serial

port #2. This string will instruct an attached Extron switcher to change to input #1.

Code examples

This section shows practical uses for both SSIs and query strings.

Before attempting to develop new Web pages, the user should have a good, working knowledge of JavaScript, HTML, and server side includes.

Example 1

In figure 4-26a, both host SSI and remote SSI commands are used within the same Web page. You will notice six SSIs: three host commands and three remote commands.

	<html>
	<head><title>Example 1</title></head>
	<h2 b>HTML Example #1</h2 b>
	<body>
	The following lines demonstrate how to read status from the IPLink Product:
	<p>
	IPLink Product Name: <b><!--#echovar="1I"--></b>	"host" SSI
	<br>	"host" SSI
	<br>	commands
	IPLink Product Description: <b><!--#echovar="2I"--></b>	commands
	IPLink Product Description: <b><!--#echovar="2I"--></b>
	<br>
	IPLink Product Part Number: <b><!--#echovar="N"--></b>
	<br><hr>
	<p>
	This example requires an Extron Crosspoint 84HVA connected to IPL T SF244
	serial
	port #1.
	<p>	"remote" SSI
	Part Number: <b><!--#echo var="W01RSN"--></b>	commands
	<br>
	Connection Info: <b><!--#echo var="W01RSI"--></b>
	<br>
	Firmware Version: <b><!--#echo var="W01RSQ"--></b>

Figure 4-26a — HTML source code document showing server side includes

IPL T SF24 and IPL T SFI244 • Communication and Control 4-31

Extron electronic SFI244 Series, IPL T SF24 user manual Query string, Code examples, Example

Models: SFI244 Series IPL T SF24

Communication and Control, cont’d

Server Side Include Using a Remote SIS command

<!--#echo var=" W 1

Hello

Figure 4-23 — Example of SSI “remote” command

Query string

URL with a Query String using a Host SIS command

W0DH

DHCP off </a>

Figure 4-24 — Example of a host query string command

URL with a Query String using a Remote SIS command

<a href="index.html ?

cmd=

Input #1

Figure 4-25 — Example of a remote query string

command

Code examples

Example 1

Figure 4-26a — HTML source code document showing server side includes