Constraints Specific To User-Defined Web Pages - Siemens SIMATIC S7-1200 Manual

You can use the software package of your choice to create your own HTML pages for use
with the Web server. Be sure that your HTML code is compliant to the HTML standards of
the W3C (World Wide Web Consortium). STEP 7 does not perform any verification of your
HTML syntax.
You can use a software package that lets you design in WYSIWYG or design layout mode,
but you need to be able to edit your HTML code in pure HTML form. Most Web authoring
tools provide this type of editing; otherwise, you can always use a simple text editor to edit
the HTML code. Include the following line in your HTML page to set the charset for the page
to UTF-8:
<meta http-equiv="content-type" content="text/html; charset=utf-8">
Also be sure to save the file from the editor in UTF-8 character encoding.
You use STEP 7 to compile everything in your HTML pages into STEP 7 data blocks. These
data blocks consist of one control data block that directs the display of the Web pages and
one or more fragment data blocks that contain the compiled Web pages. Be aware that
extensive sets of HTML pages, particularly those with lots of images, require a significant
amount of load memory space for the fragment DBs. If the internal load memory of your CPU
is not sufficient for your user-defined Web pages, use a memory card to provide external
load memory.
To program your HTML code to use data from the S7-1200, you include AWP commands as
HTML comments. When finished, save your HTML pages to your PC and note the folder
path where you save them.
Note
The file size limit for HTML files containing AWP command is 64 kilobytes. You must keep
your file size below this limit.
Refreshing user-defined Web pages
User-defined Web pages do not automatically refresh. It is your choice whether to program
the HTML to refresh the page or not. For pages that display PLC data, refreshing periodically
keeps the data current. For HTML pages that serve as forms for data entry, refreshing can
interfere with the user entering data. If you want your entire page to automatically refresh,
you can add this line to your HTML header, where "10" is the number of seconds between
refreshes:
<meta http-equiv="Refresh" content="10">
You can also use JavaScript or other HTML techniques to control page or data refreshing.
For this, refer to documentation on HTML and JavaScript.
9.3.2

Constraints specific to user-defined Web pages

The constraints for standard Web pages also apply to user-defined Web pages. In addition,
user-defined Web pages have some specific considerations.
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Manual, 03/2014, A5E02486774-AF
Web server for easy Internet connectivity
9.3 Easy to create user-defined web pages
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