C# - GPS Bricklet 2.0

This is the description of the C# API bindings for the GPS Bricklet 2.0. General information and technical specifications for the GPS Bricklet 2.0 are summarized in its hardware description.

An installation guide for the C# API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Simple

Download (ExampleSimple.cs)

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using System;
using Tinkerforge;

class Example
{
    private static string HOST = "localhost";
    private static int PORT = 4223;
    private static string UID = "XYZ"; // Change XYZ to the UID of your GPS Bricklet 2.0

    static void Main()
    {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletGPSV2 gps = new BrickletGPSV2(UID, ipcon); // Create device object

        ipcon.Connect(HOST, PORT); // Connect to brickd
        // Don't use device before ipcon is connected

        // Get current coordinates
        long latitude, longitude; char ns, ew;
        gps.GetCoordinates(out latitude, out ns, out longitude, out ew);

        Console.WriteLine("Latitude: " + latitude/1000000.0 + " °");
        Console.WriteLine("N/S: " + ns);
        Console.WriteLine("Longitude: " + longitude/1000000.0 + " °");
        Console.WriteLine("E/W: " + ew);

        Console.WriteLine("Press enter to exit");
        Console.ReadLine();
        ipcon.Disconnect();
    }
}

Callback

Download (ExampleCallback.cs)

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using System;
using Tinkerforge;

class Example
{
    private static string HOST = "localhost";
    private static int PORT = 4223;
    private static string UID = "XYZ"; // Change XYZ to the UID of your GPS Bricklet 2.0

    // Callback function for coordinates callback
    static void CoordinatesCB(BrickletGPSV2 sender, long latitude, char ns,
                              long longitude, char ew)
    {
        Console.WriteLine("Latitude: " + latitude/1000000.0 + " °");
        Console.WriteLine("N/S: " + ns);
        Console.WriteLine("Longitude: " + longitude/1000000.0 + " °");
        Console.WriteLine("E/W: " + ew);
        Console.WriteLine("");
    }

    static void Main()
    {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletGPSV2 gps = new BrickletGPSV2(UID, ipcon); // Create device object

        ipcon.Connect(HOST, PORT); // Connect to brickd
        // Don't use device before ipcon is connected

        // Register coordinates callback to function CoordinatesCB
        gps.CoordinatesCallback += 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 enter to exit");
        Console.ReadLine();
        ipcon.Disconnect();
    }
}

API

Generally, every method of the C# bindings that returns a value can throw a Tinkerforge.TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody plugs the device out). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

Since C# does not support multiple return values directly, we use the out keyword to return multiple values from a method.

The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.

All methods listed below are thread-safe.

Basic Functions

public class BrickletGPSV2(String uid, IPConnection ipcon)

Creates an object with the unique device ID uid:

BrickletGPSV2 gpsV2 = new BrickletGPSV2("YOUR_DEVICE_UID", ipcon);

This object can then be used after the IP Connection is connected (see examples above).

public void GetCoordinates(out long latitude, out char ns, out long longitude, out char ew)

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).

This data is only valid if there is currently a fix as indicated by GetStatus().

public void GetStatus(out bool hasFix, out byte satellitesView)

Returns if a fix is currently available as well as the, the number of satellites that are in view.

There is also a green LED on the Bricklet that indicates the fix status.

public void GetAltitude(out int altitude, out int geoidalSeparation)

Returns the current altitude and corresponding geoidal separation.

Both values are given in cm.

This data is only valid if there is currently a fix as indicated by GetStatus().

public void GetMotion(out long course, out long speed)

Returns the current course and speed. Course is given in hundredths degree and speed is given in hundredths km/h. 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().

public void GetDateTime(out long date, out long time)

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 14.05.13 as date and 195923568 means 19:59:23.568 as time.

public void GetSatelliteSystemStatus(byte satelliteSystem, out byte[] satelliteNumbers, out byte fix, out int pdop, out int hdop, out int vdop)

Returns the

  • satellite numbers list (up to 12 items)
  • fix value,
  • PDOP value,
  • HDOP value and
  • VDOP value

for a given satellite system. Currently GPS and GLONASS are supported, Galileo is not yet supported.

The GPS and GLONASS satellites have unique numbers and the satellite list gives the numbers of the satellites that are currently utilized. The number 0 is not a valid satellite number and can be ignored in the list.

The following constants are available for this function:

  • BrickletGPSV2.SATELLITE_SYSTEM_GPS = 0
  • BrickletGPSV2.SATELLITE_SYSTEM_GLONASS = 1
  • BrickletGPSV2.SATELLITE_SYSTEM_GALILEO = 2
  • BrickletGPSV2.FIX_NO_FIX = 1
  • BrickletGPSV2.FIX_2D_FIX = 2
  • BrickletGPSV2.FIX_3D_FIX = 3
public void GetSatelliteStatus(byte satelliteSystem, byte satelliteNumber, out short elevation, out short azimuth, out short snr)

Returns the current

  • elevation (0° - 90°),
  • azimuth (0° - 359°) and
  • SNR (0dB - 99dB)

for a given satellite and satellite system.

The satellite number here always goes from 1 to 32. For GLONASS it corresponds to the satellites 65-96.

Galileo is not yet supported.

The following constants are available for this function:

  • BrickletGPSV2.SATELLITE_SYSTEM_GPS = 0
  • BrickletGPSV2.SATELLITE_SYSTEM_GLONASS = 1
  • BrickletGPSV2.SATELLITE_SYSTEM_GALILEO = 2

Advanced Functions

public void Restart(byte restartType)

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:

  • BrickletGPSV2.RESTART_TYPE_HOT_START = 0
  • BrickletGPSV2.RESTART_TYPE_WARM_START = 1
  • BrickletGPSV2.RESTART_TYPE_COLD_START = 2
  • BrickletGPSV2.RESTART_TYPE_FACTORY_RESET = 3
public void SetFixLEDConfig(byte config)

Sets the fix LED configuration. By default the LED shows if the Bricklet got a GPS fix yet. If a fix is established the LED turns on. If there is no fix then the LED is turned off.

You can also turn the LED permanently on/off, show a heartbeat or let it blink in sync with the PPS (pulse per second) output of the GPS module.

If the Bricklet is in bootloader mode, the LED is off.

The following constants are available for this function:

  • BrickletGPSV2.FIX_LED_CONFIG_OFF = 0
  • BrickletGPSV2.FIX_LED_CONFIG_ON = 1
  • BrickletGPSV2.FIX_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletGPSV2.FIX_LED_CONFIG_SHOW_FIX = 3
  • BrickletGPSV2.FIX_LED_CONFIG_SHOW_PPS = 4
public byte GetFixLEDConfig()

Returns the configuration as set by SetFixLEDConfig()

The following constants are available for this function:

  • BrickletGPSV2.FIX_LED_CONFIG_OFF = 0
  • BrickletGPSV2.FIX_LED_CONFIG_ON = 1
  • BrickletGPSV2.FIX_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletGPSV2.FIX_LED_CONFIG_SHOW_FIX = 3
  • BrickletGPSV2.FIX_LED_CONFIG_SHOW_PPS = 4
public void SetSBASConfig(byte sbasConfig)

If SBAS is enabled, the position accuracy increases (if SBAS satellites are in view), but the update rate is limited to 5Hz. With SBAS disabled the update rate is increased to 10Hz.

By default SBAS is enabled and the update rate is 5Hz.

The following constants are available for this function:

  • BrickletGPSV2.SBAS_ENABLED = 0
  • BrickletGPSV2.SBAS_DISABLED = 1

New in version 2.0.2 (Plugin).

public byte GetSBASConfig()

Returns the SBAS configuration as set by SetSBASConfig()

The following constants are available for this function:

  • BrickletGPSV2.SBAS_ENABLED = 0
  • BrickletGPSV2.SBAS_DISABLED = 1

New in version 2.0.2 (Plugin).

public byte[] GetAPIVersion()

Returns the version of the API definition (major, minor, revision) 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.

public bool GetResponseExpected(byte functionId)

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 send and errors are silently ignored, because they cannot be detected.

See SetResponseExpected() for the list of function ID constants available for this function.

public void SetResponseExpected(byte functionId, bool responseExpected)

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 send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BrickletGPSV2.FUNCTION_RESTART = 6
  • BrickletGPSV2.FUNCTION_SET_FIX_LED_CONFIG = 9
  • BrickletGPSV2.FUNCTION_SET_COORDINATES_CALLBACK_PERIOD = 11
  • BrickletGPSV2.FUNCTION_SET_STATUS_CALLBACK_PERIOD = 13
  • BrickletGPSV2.FUNCTION_SET_ALTITUDE_CALLBACK_PERIOD = 15
  • BrickletGPSV2.FUNCTION_SET_MOTION_CALLBACK_PERIOD = 17
  • BrickletGPSV2.FUNCTION_SET_DATE_TIME_CALLBACK_PERIOD = 19
  • BrickletGPSV2.FUNCTION_SET_SBAS_CONFIG = 27
  • BrickletGPSV2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletGPSV2.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletGPSV2.FUNCTION_RESET = 243
  • BrickletGPSV2.FUNCTION_WRITE_UID = 248
public void SetResponseExpectedAll(bool responseExpected)

Changes the response expected flag for all setter and callback configuration functions of this device at once.

public void GetSPITFPErrorCount(out long errorCountAckChecksum, out long errorCountMessageChecksum, out long errorCountFrame, out long errorCountOverflow)

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

public byte SetBootloaderMode(byte mode)

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

  • BrickletGPSV2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletGPSV2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletGPSV2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletGPSV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletGPSV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BrickletGPSV2.BOOTLOADER_STATUS_OK = 0
  • BrickletGPSV2.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletGPSV2.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletGPSV2.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletGPSV2.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletGPSV2.BOOTLOADER_STATUS_CRC_MISMATCH = 5
public byte GetBootloaderMode()

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

  • BrickletGPSV2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletGPSV2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletGPSV2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletGPSV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletGPSV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
public void SetWriteFirmwarePointer(long pointer)

Sets the firmware pointer for WriteFirmware(). The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

public byte WriteFirmware(byte[] data)

Writes 64 Bytes of firmware at the position as written by SetWriteFirmwarePointer() before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

public void SetStatusLEDConfig(byte config)

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

  • BrickletGPSV2.STATUS_LED_CONFIG_OFF = 0
  • BrickletGPSV2.STATUS_LED_CONFIG_ON = 1
  • BrickletGPSV2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletGPSV2.STATUS_LED_CONFIG_SHOW_STATUS = 3
public byte GetStatusLEDConfig()

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

  • BrickletGPSV2.STATUS_LED_CONFIG_OFF = 0
  • BrickletGPSV2.STATUS_LED_CONFIG_ON = 1
  • BrickletGPSV2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletGPSV2.STATUS_LED_CONFIG_SHOW_STATUS = 3
public short GetChipTemperature()

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

public void Reset()

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

public void WriteUID(long uid)

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

public long ReadUID()

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

public void GetIdentity(out string uid, out string connectedUid, out char position, out byte[] hardwareVersion, out byte[] firmwareVersion, out int deviceIdentifier)

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' or 'd'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

public void SetCoordinatesCallbackPeriod(long period)

Sets the period in ms 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.

The default value is 0.

public long GetCoordinatesCallbackPeriod()

Returns the period as set by SetCoordinatesCallbackPeriod().

public void SetStatusCallbackPeriod(long period)

Sets the period in ms 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.

The default value is 0.

public long GetStatusCallbackPeriod()

Returns the period as set by SetStatusCallbackPeriod().

public void SetAltitudeCallbackPeriod(long period)

Sets the period in ms 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.

The default value is 0.

public long GetAltitudeCallbackPeriod()

Returns the period as set by SetAltitudeCallbackPeriod().

public void SetMotionCallbackPeriod(long period)

Sets the period in ms 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.

The default value is 0.

public long GetMotionCallbackPeriod()

Returns the period as set by SetMotionCallbackPeriod().

public void SetDateTimeCallbackPeriod(long period)

Sets the period in ms 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.

The default value is 0.

public long GetDateTimeCallbackPeriod()

Returns the period as set by SetDateTimeCallbackPeriod().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by appending your callback handler to the corresponding event:

void MyCallback(BrickletGPSV2 sender, int value)
{
    System.Console.WriteLine("Value: " + value);
}

gpsV2.ExampleCallback += MyCallback;

The available events 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.

public event PulsePerSecondCallback(BrickletGPSV2 sender)

This callback is triggered precisely once per second, see PPS.

The precision of two subsequent pulses will be skewed because of the latency in the USB/RS485/Ethernet connection. But in the long run this will be very precise. For example a count of 3600 pulses will take exactly 1 hour.

public event CoordinatesCallback(BrickletGPSV2 sender, long latitude, char ns, long longitude, char ew)

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().

public event StatusCallback(BrickletGPSV2 sender, bool hasFix, byte satellitesView)

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.

public event AltitudeCallback(BrickletGPSV2 sender, int altitude, int geoidalSeparation)

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().

public event MotionCallback(BrickletGPSV2 sender, long course, long speed)

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().

public event DateTimeCallback(BrickletGPSV2 sender, long date, long time)

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.

Constants

public int DEVICE_IDENTIFIER

This constant is used to identify a GPS Bricklet 2.0.

The GetIdentity() function and the EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

public string DEVICE_DISPLAY_NAME

This constant represents the human readable name of a GPS Bricklet 2.0.