Yoctopuce Yocto-Display, Руководство пользователя

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// Get access to your device, through the VirtualHub running locally
yRegisterHub ( 'http://127.0.0.1:4444/' , $errmsg );
$display = yFindDisplay ( "YD128X32-123456.display" );
// Check that the module is online to handle hot-plug
if( display -> isOnline ())
{
// Use display->get_displayLayer(), ...
}
Let's look at these lines in more details.
yocto_api.php and yocto_display.php
These two PHP includes provides access to the functions allowing you to manage Yoctopuce
modules.
yocto_api.php
must always be included,
yocto_display.php
is necessary to
manage modules containing a display, such as Yocto-Display.
yRegisterHub
The
yRegisterHub
function allows you to indicate on which machine the Yoctopuce modules are
located, more precisely on which machine the VirtualHub software is running. In our case, the
127.0.0.1:4444
address indicates the local machine, port
4444
(the standard port used by
Yoctopuce). You can very well modify this address, and enter the address of another machine on
which the VirtualHub software is running.
yFindDisplay
The
yFindDisplay
function allows you to find a display from the serial number of the module on
which it resides and from its function name. You can use logical names as well, as long as you have
initialized them. Let us imagine a Yocto-Display module with serial number
YD128X32-123456 which
you have named " MyModule ", and for which you have given the display function the name
" MyFunction ". The following five calls are strictly equivalent, as long as " MyFunction " is defined only
once.
$display = yFindDisplay ( "YD128X32-123456.display" );
$display = yFindDisplay ( "YD128X32-123456.MyFunction" );
$display = yFindDisplay ( "MyModule.display" );
$display = yFindDisplay ( "MyModule.MyFunction" );
$display = yFindDisplay ( "MyFunction" );
yFindDisplay
returns an object which you can then use at will to control the display.
isOnline
The
isOnline()
method of the object returned by
yFindDisplay
allows you to know if the
corresponding module is present and in working order.
get_displayLayer
The
get_diplayLayer()
method of the object returned by
YFindDisplay
allows you to
retrieve the object corresponding to one of the screen layers. This object implements all the graphical
routines.
A real example
Open your preferred text editor
4
, copy the code sample below, save it with the Yoctopuce library files
in a location which is accessible to you web server, then use your preferred web browser to access
this page. The code is also provided in the directory
Examples/Doc-GettingStarted-Yocto-Display
of the Yoctopuce library.
In this example, you will recognize the functions explained above, but this time used with all side
materials needed to make it work nicely as a small demo.
4
If you do not have a text editor, use Notepad rather than Microsoft Word.
10. Using Yocto-Display with PHP
48 www.yoctopuce.com