Yoctopuce Yocto-GPS, User Manual

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Then add in the same manner the
yapi.dll
DLL, located in the
Sources/dll
directory
4
. Then,
from the Solution Explorer window, right click on the DLL, select Properties and in the Properties
panel, set the Copy to output folder to always . You are now ready to use your Yoctopuce modules
from Visual Studio.
In order to keep them simple, all the examples provided in this documentation are console
applications. Naturally, the libraries function in a strictly identical manner if you integrate them in an
application with a graphical interface.
11.3. Control of the Latitude function
A few lines of code are enough to use a Yocto-GPS. Here is the skeleton of a Visual Basic code
snipplet to use the Latitude function.
[ ... ]
Dim errmsg As String errmsg
Dim latitude As YLatitude
REM Get access to your device, connected locally on USB for instance
yRegisterHub ( "usb" , errmsg )
latitude = yFindLatitude ( "YGNSSMK1-123456.latitude" )
REM Hot-plug is easy: just check that the device is online
If ( latitude. isOnline ()) Then
REM Use latitude.get_currentValue(), ...
End If
Let's look at these lines in more details.
yRegisterHub
The
yRegisterHub
function initializes the Yoctopuce API and indicates where the modules should
be looked for. When used with the parameter
"usb"
, it will use the modules locally connected to the
computer running the library. If the initialization does not succeed, this function returns a value
different from
YAPI_SUCCESS
and
errmsg
contains the error message.
yFindLatitude
The
yFindLatitude
function allows you to find a latitude sensor 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-GPS module with serial number
YGNSSMK1-123456 which you have named " MyModule ", and for which you have given the latitude
function the name " MyFunction ". The following five calls are strictly equivalent, as long as
" MyFunction " is defined only once.
latitude = yFindLatitude ( "YGNSSMK1-123456.latitude" )
latitude = yFindLatitude ( "YGNSSMK1-123456.MyFunction" )
latitude = yFindLatitude ( "MyModule.latitude" )
latitude = yFindLatitude ( "MyModule.MyFunction" )
latitude = yFindLatitude ( "MyFunction" )
yFindLatitude
returns an object which you can then use at will to control the latitude sensor.
isOnline
The
isOnline()
method of the object returned by
yFindLatitude
allows you to know if the
corresponding module is present and in working order.
get_latitude
The
get_latitude()
method of the object returned by
yFindGps
provides the latitude currently
measured by the Yocto-GPS. The value returned is a string, the format will vary according to the
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Remember to change the filter of the selection window, otherwise the DLL will not show.
11. Using Yocto-GPS with Visual Basic .NET
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