Yoctopuce Yocto-GPS, User Manual

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[ ... ]
errmsg=YRefParam ()
#Get access to your device, connected locally on USB for instance
YAPI. RegisterHub ( "usb" ,errmsg )
latitude = YLatitude. FindLatitude ( "YGNSSMK1-123456.latitude" )
# Hot-plug is easy: just check that the device is online
if latitude. isOnline () :
#Use latitude.get_currentValue()
...
[ ... ]
Let's look at these lines in more details.
YAPI.RegisterHub
The
yAPI.RegisterHub
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.
YLatitude.FindLatitude
The
YLatitude.FindLatitude
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 = YLatitude. FindLatitude ( "YGNSSMK1-123456.latitude" )
latitude = YLatitude. FindLatitude ( "YGNSSMK1-123456.MyFunction" )
latitude = YLatitude. FindLatitude ( "MyModule.latitude" )
latitude = YLatitude. FindLatitude ( "MyModule.MyFunction" )
latitude = YLatitude. FindLatitude ( "MyFunction" )
YLatitude.FindLatitude
returns an object which you can then use at will to control the
latitude sensor.
isOnline
The
isOnline()
method of the object returned by
YLatitude.FindLatitude
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
YGps.FindGps
provides the latitude
currently measured by the Yocto-GPS. The value returned is a string, the format will vary according
to the Yocto-GPS configuration. To get a floating point value, no matter the configuartion, use the
YLatitude Class.
A real example
Launch Python and open the corresponding sample script provided in the directory Examples/Doc-
GettingStarted-Yocto-GPS 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.
#!/usr/bin/python
# -*- coding: utf-8 -*-
import os , sys
from yocto_api import *
from yocto_gps import *
14. Using the Yocto-GPS with Python
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