Programming The Www Instruction For User-Defined Web Pages - Siemens S7-1200 System Manual

Web server
11.6 User-defined Web pages
9. Keep the default for the Web DB number, or enter a number of your choice. This is the
DB number of the control DB that controls display of the Web pages.
10.Keep the default for the fragment DB start number, or enter a number of your choice. This
is the first of the fragment DBs that contains the Web pages.
Generating program blocks
When you click the "Generate blocks" button, STEP 7 generates data blocks from the HTML
pages in the HTML source directory that you specified and a control data block for the
operation of your Web pages. You can set these attributes as needed for your application
(Page 642). STEP 7 also generates a set of fragment data blocks to hold the representation
of all of your HTML pages. When you generate the data blocks, STEP 7 updates the
properties to display the control data block number, and the number of the first of the
fragment data blocks. After you generate the data blocks, your user-defined Web pages are
a part of your STEP 7 program. The blocks corresponding to these pages appear in the Web
server folder, which is in the System blocks folder under Program blocks in the project
navigation tree.
Deleting program blocks
To delete data blocks that you have previously generated, click the "Delete data blocks"
button. STEP 7 deletes the control data block and all of the fragment data blocks from your
project that correspond to user-defined Web pages.
11.6.4

Programming the WWW instruction for user-defined web pages

Your STEP 7 user program must include and execute the WWW instruction in order for the
user-defined Web pages to be accessible from the standard Web pages. The control data
block is the input parameter to the WWW instruction and specifies the content of the pages
as represented in the fragment data blocks, as well as state and control information. STEP 7
creates the control data block when you click the "Create blocks" button in the configuration
of user-defined Web pages (Page 641).
Programming the WWW instruction
The STEP 7 program must execute the WWW instruction for the user-defined Web pages to
be accessible from the standard Web pages. You might want the user-defined Web pages
available only under certain circumstances as dictated by your application requirements and
preferences. In this case, your program logic can control when to call the WWW instruction.
Table 11- 3 WWW instruction
LAD / FBD
642
SCL
ret_val := WWW(
ctrl_db:=_uint_in_);
Description
Provides access to user-defined Web pages
from standard Web pages
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG