This is the description of the Visual Basic .NET API bindings for the GPS Bricklet. General information and technical specifications for the GPS Bricklet are summarized in its hardware description.
An installation guide for the Visual Basic .NET API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 | Imports System
Imports Tinkerforge
Module ExampleSimple
Const HOST As String = "localhost"
Const PORT As Integer = 4223
Const UID As String = "XYZ" ' Change XYZ to the UID of your GPS Bricklet
Sub Main()
Dim ipcon As New IPConnection() ' Create IP connection
Dim gps As New BrickletGPS(UID, ipcon) ' Create device object
ipcon.Connect(HOST, PORT) ' Connect to brickd
' Don't use device before ipcon is connected
' Get current coordinates
Dim latitude, longitude As Long
Dim ns, ew As Char
Dim pdop, hdop, vdop, epe As Integer
gps.GetCoordinates(latitude, ns, longitude, ew, pdop, hdop, vdop, epe)
Console.WriteLine("Latitude: " + (latitude/1000000.0).ToString() + " °")
Console.WriteLine("N/S: " + ns)
Console.WriteLine("Longitude: " + (longitude/1000000.0).ToString() + " °")
Console.WriteLine("E/W: " + ew)
Console.WriteLine("Press key to exit")
Console.ReadLine()
ipcon.Disconnect()
End Sub
End Module
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 | Imports System
Imports Tinkerforge
Module ExampleCallback
Const HOST As String = "localhost"
Const PORT As Integer = 4223
Const UID As String = "XYZ" ' Change XYZ to the UID of your GPS Bricklet
' Callback subroutine for coordinates callback
Sub CoordinatesCB(ByVal sender As BrickletGPS, ByVal latitude As Long, _
ByVal ns As Char, ByVal longitude As Long, ByVal ew As Char, _
ByVal pdop As Integer, ByVal hdop As Integer, _
ByVal vdop As Integer, ByVal epe As Integer)
Console.WriteLine("Latitude: " + (latitude/1000000.0).ToString() + " °")
Console.WriteLine("N/S: " + ns)
Console.WriteLine("Longitude: " + (longitude/1000000.0).ToString() + " °")
Console.WriteLine("E/W: " + ew)
Console.WriteLine("")
End Sub
Sub Main()
Dim ipcon As New IPConnection() ' Create IP connection
Dim gps As New BrickletGPS(UID, ipcon) ' Create device object
ipcon.Connect(HOST, PORT) ' Connect to brickd
' Don't use device before ipcon is connected
' Register coordinates callback to subroutine CoordinatesCB
AddHandler gps.CoordinatesCallback, AddressOf CoordinatesCB
' Set period for coordinates callback to 1s (1000ms)
' Note: The coordinates callback is only called every second
' if the coordinates has changed since the last call!
gps.SetCoordinatesCallbackPeriod(1000)
Console.WriteLine("Press key to exit")
Console.ReadLine()
ipcon.Disconnect()
End Sub
End Module
|
Since Visual Basic .NET does not support multiple return values directly, we
use the ByRef
keyword to return multiple values from a function.
All functions and procedures listed below are thread-safe.
BrickletGPS
(ByVal uid As String, ByVal ipcon As IPConnection)¶Creates an object with the unique device ID uid
:
Dim gps As New BrickletGPS("YOUR_DEVICE_UID", ipcon)
This object can then be used after the IP Connection is connected.
BrickletGPS.
GetCoordinates
(ByRef latitude As Long, ByRef ns As Char, ByRef longitude As Long, ByRef ew As Char, ByRef pdop As Integer, ByRef hdop As Integer, ByRef vdop As Integer, ByRef epe As Integer)¶Output Parameters: |
|
---|
Returns the GPS coordinates. Latitude and longitude are given in the
DD.dddddd°
format, the value 57123468 means 57.123468°.
The parameter ns
and ew
are the cardinal directions for
latitude and longitude. Possible values for ns
and ew
are 'N', 'S', 'E'
and 'W' (north, south, east and west).
PDOP, HDOP and VDOP are the dilution of precision (DOP) values. They specify the additional multiplicative effect of GPS satellite geometry on GPS precision. See here for more information.
EPE is the "Estimated Position Error". This is not the absolute maximum error, it is the error with a specific confidence. See here for more information.
This data is only valid if there is currently a fix as indicated by
GetStatus()
.
BrickletGPS.
GetStatus
(ByRef fix As Byte, ByRef satellitesView As Byte, ByRef satellitesUsed As Byte)¶Output Parameters: |
|
---|
Returns the current fix status, the number of satellites that are in view and the number of satellites that are currently used.
Possible fix status values can be:
Value | Description |
---|---|
1 | No Fix, GetCoordinates() , GetAltitude() and GetMotion() return invalid data |
2 | 2D Fix, only GetCoordinates() and GetMotion() return valid data |
3 | 3D Fix, GetCoordinates() , GetAltitude() and GetMotion() return valid data |
There is also a blue LED on the Bricklet that indicates the fix status.
The following constants are available for this function:
For fix:
BrickletGPS.
GetAltitude
(ByRef altitude As Integer, ByRef geoidalSeparation As Integer)¶Output Parameters: |
|
---|
Returns the current altitude and corresponding geoidal separation.
This data is only valid if there is currently a fix as indicated by
GetStatus()
.
BrickletGPS.
GetMotion
(ByRef course As Long, ByRef speed As Long)¶Output Parameters: |
|
---|
Returns the current course and speed. A course of 0° means the Bricklet is traveling north bound and 90° means it is traveling east bound.
Please note that this only returns useful values if an actual movement is present.
This data is only valid if there is currently a fix as indicated by
GetStatus()
.
BrickletGPS.
GetDateTime
(ByRef date As Long, ByRef time As Long)¶Output Parameters: |
|
---|
Returns the current date and time. The date is
given in the format ddmmyy
and the time is given
in the format hhmmss.sss
. For example, 140713 means
14.07.13 as date and 195923568 means 19:59:23.568 as time.
BrickletGPS.
Restart
(ByVal restartType As Byte)¶Parameters: |
|
---|
Restarts the GPS Bricklet, the following restart types are available:
Value | Description |
---|---|
0 | Hot start (use all available data in the NV store) |
1 | Warm start (don't use ephemeris at restart) |
2 | Cold start (don't use time, position, almanacs and ephemeris at restart) |
3 | Factory reset (clear all system/user configurations at restart) |
The following constants are available for this function:
For restartType:
BrickletGPS.
GetIdentity
(ByRef uid As String, ByRef connectedUid As String, ByRef position As Char, ByRef hardwareVersion() As Byte, ByRef firmwareVersion() As Byte, ByRef deviceIdentifier As Integer)¶Output Parameters: |
|
---|
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
BrickletGPS.
SetCoordinatesCallbackPeriod
(ByVal period As Long)¶Parameters: |
|
---|
Sets the period with which the CoordinatesCallback
callback is triggered
periodically. A value of 0 turns the callback off.
The CoordinatesCallback
callback is only triggered if the coordinates changed
since the last triggering.
BrickletGPS.
GetCoordinatesCallbackPeriod
() As Long¶Returns: |
|
---|
Returns the period as set by SetCoordinatesCallbackPeriod()
.
BrickletGPS.
SetStatusCallbackPeriod
(ByVal period As Long)¶Parameters: |
|
---|
Sets the period with which the StatusCallback
callback is triggered
periodically. A value of 0 turns the callback off.
The StatusCallback
callback is only triggered if the status changed since the
last triggering.
BrickletGPS.
GetStatusCallbackPeriod
() As Long¶Returns: |
|
---|
Returns the period as set by SetStatusCallbackPeriod()
.
BrickletGPS.
SetAltitudeCallbackPeriod
(ByVal period As Long)¶Parameters: |
|
---|
Sets the period with which the AltitudeCallback
callback is triggered
periodically. A value of 0 turns the callback off.
The AltitudeCallback
callback is only triggered if the altitude changed since
the last triggering.
BrickletGPS.
GetAltitudeCallbackPeriod
() As Long¶Returns: |
|
---|
Returns the period as set by SetAltitudeCallbackPeriod()
.
BrickletGPS.
SetMotionCallbackPeriod
(ByVal period As Long)¶Parameters: |
|
---|
Sets the period with which the MotionCallback
callback is triggered
periodically. A value of 0 turns the callback off.
The MotionCallback
callback is only triggered if the motion changed since the
last triggering.
BrickletGPS.
GetMotionCallbackPeriod
() As Long¶Returns: |
|
---|
Returns the period as set by SetMotionCallbackPeriod()
.
BrickletGPS.
SetDateTimeCallbackPeriod
(ByVal period As Long)¶Parameters: |
|
---|
Sets the period with which the DateTimeCallback
callback is triggered
periodically. A value of 0 turns the callback off.
The DateTimeCallback
callback is only triggered if the date or time changed
since the last triggering.
BrickletGPS.
GetDateTimeCallbackPeriod
() As Long¶Returns: |
|
---|
Returns the period as set by SetDateTimeCallbackPeriod()
.
Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a procedure to an callback property of the device object:
Sub MyCallback(ByVal sender As BrickletGPS, ByVal value As Short) Console.WriteLine("Value: {0}", value) End Sub AddHandler gps.ExampleCallback, AddressOf MyCallback
The available callback property and their type of parameters are described below.
Note
Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.
BrickletGPS.
CoordinatesCallback
(ByVal sender As BrickletGPS, ByVal latitude As Long, ByVal ns As Char, ByVal longitude As Long, ByVal ew As Char, ByVal pdop As Integer, ByVal hdop As Integer, ByVal vdop As Integer, ByVal epe As Integer)¶Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
SetCoordinatesCallbackPeriod()
. The parameters are the same
as for GetCoordinates()
.
The CoordinatesCallback
callback is only triggered if the coordinates changed
since the last triggering and if there is currently a fix as indicated by
GetStatus()
.
BrickletGPS.
StatusCallback
(ByVal sender As BrickletGPS, ByVal fix As Byte, ByVal satellitesView As Byte, ByVal satellitesUsed As Byte)¶Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
SetStatusCallbackPeriod()
. The parameters are the same
as for GetStatus()
.
The StatusCallback
callback is only triggered if the status changed since the
last triggering.
The following constants are available for this function:
For fix:
BrickletGPS.
AltitudeCallback
(ByVal sender As BrickletGPS, ByVal altitude As Integer, ByVal geoidalSeparation As Integer)¶Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
SetAltitudeCallbackPeriod()
. The parameters are the same
as for GetAltitude()
.
The AltitudeCallback
callback is only triggered if the altitude changed since
the last triggering and if there is currently a fix as indicated by
GetStatus()
.
BrickletGPS.
MotionCallback
(ByVal sender As BrickletGPS, ByVal course As Long, ByVal speed As Long)¶Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
SetMotionCallbackPeriod()
. The parameters are the same
as for GetMotion()
.
The MotionCallback
callback is only triggered if the motion changed since the
last triggering and if there is currently a fix as indicated by
GetStatus()
.
BrickletGPS.
DateTimeCallback
(ByVal sender As BrickletGPS, ByVal date As Long, ByVal time As Long)¶Callback Parameters: |
|
---|
This callback is triggered periodically with the period that is set by
SetDateTimeCallbackPeriod()
. The parameters are the same
as for GetDateTime()
.
The DateTimeCallback
callback is only triggered if the date or time changed
since the last triggering.
Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.
BrickletGPS.
GetAPIVersion
() As Byte()¶Output Parameters: |
|
---|
Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.
BrickletGPS.
GetResponseExpected
(ByVal functionId As Byte) As Boolean¶Parameters: |
|
---|---|
Returns: |
|
Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.
For getter functions this is enabled by default and cannot be disabled,
because those functions will always send a response. For callback configuration
functions it is enabled by default too, but can be disabled by
SetResponseExpected()
. For setter functions it is disabled by default
and can be enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For functionId:
BrickletGPS.
SetResponseExpected
(ByVal functionId As Byte, ByVal responseExpected As Boolean)¶Parameters: |
|
---|
Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For functionId:
BrickletGPS.
SetResponseExpectedAll
(ByVal responseExpected As Boolean)¶Parameters: |
|
---|
Changes the response expected flag for all setter and callback configuration functions of this device at once.
BrickletGPS.
DEVICE_IDENTIFIER
¶This constant is used to identify a GPS Bricklet.
The GetIdentity()
function and the
IPConnection.EnumerateCallback
callback of the IP Connection have a deviceIdentifier
parameter to specify
the Brick's or Bricklet's type.
BrickletGPS.
DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a GPS Bricklet.