C/C++ for Microcontrollers - GPS Bricklet 2.0

This is the description of the C/C++ for Microcontrollers 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/C++ for Microcontrollers API bindings is part of their general description.

Examples

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

Simple

Download (example_simple.c)

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// This example is not self-contained.
// It requires usage of the example driver specific to your platform.
// See the HAL documentation.

#include "src/bindings/hal_common.h"
#include "src/bindings/bricklet_gps_v2.h"

void check(int rc, const char *msg);
void example_setup(TF_HAL *hal);
void example_loop(TF_HAL *hal);

static TF_GPSV2 gps;

void example_setup(TF_HAL *hal) {
    // Create device object
    check(tf_gps_v2_create(&gps, NULL, hal), "create device object");

    // Get current coordinates
    uint32_t latitude, longitude; char ns, ew;
    check(tf_gps_v2_get_coordinates(&gps, &latitude, &ns, &longitude,
                                    &ew), "get coordinates");

    tf_hal_printf("Latitude: %d 1/%d °\n", latitude, 1000000);
    tf_hal_printf("N/S: %c\n", ns);
    tf_hal_printf("Longitude: %d 1/%d °\n", longitude, 1000000);
    tf_hal_printf("E/W: %c\n", ew);
}

void example_loop(TF_HAL *hal) {
    // Poll for callbacks
    tf_hal_callback_tick(hal, 0);
}

Callback

Download (example_callback.c)

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// This example is not self-contained.
// It requires usage of the example driver specific to your platform.
// See the HAL documentation.

#include "src/bindings/hal_common.h"
#include "src/bindings/bricklet_gps_v2.h"

void check(int rc, const char *msg);
void example_setup(TF_HAL *hal);
void example_loop(TF_HAL *hal);

// Callback function for coordinates callback
static void coordinates_handler(TF_GPSV2 *device, uint32_t latitude, char ns,
                                uint32_t longitude, char ew, void *user_data) {
    (void)device; (void)user_data; // avoid unused parameter warning

    tf_hal_printf("Latitude: %d 1/%d °\n", latitude, 1000000);
    tf_hal_printf("N/S: %c\n", ns);
    tf_hal_printf("Longitude: %d 1/%d °\n", longitude, 1000000);
    tf_hal_printf("E/W: %c\n", ew);
    tf_hal_printf("\n");
}

static TF_GPSV2 gps;

void example_setup(TF_HAL *hal) {
    // Create device object
    check(tf_gps_v2_create(&gps, NULL, hal), "create device object");

    // Register coordinates callback to function coordinates_handler
    tf_gps_v2_register_coordinates_callback(&gps,
                                            coordinates_handler,
                                            NULL);

    // 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!
    check(tf_gps_v2_set_coordinates_callback_period(&gps, 1000), "set coordinates callback period");
}

void example_loop(TF_HAL *hal) {
    // Poll for callbacks
    tf_hal_callback_tick(hal, 0);
}

API

Most functions of the C/C++ bindings for microcontrollers return an error code (e_code).

Possible error codes are:

  • TF_E_OK = 0
  • TF_E_TIMEOUT = -1
  • TF_E_INVALID_PARAMETER = -2
  • TF_E_NOT_SUPPORTED = -3
  • TF_E_UNKNOWN_ERROR_CODE = -4
  • TF_E_STREAM_OUT_OF_SYNC = -5
  • TF_E_INVALID_CHAR_IN_UID = -6
  • TF_E_UID_TOO_LONG = -7
  • TF_E_UID_OVERFLOW = -8
  • TF_E_TOO_MANY_DEVICES = -9
  • TF_E_DEVICE_NOT_FOUND = -10
  • TF_E_WRONG_DEVICE_TYPE = -11
  • TF_E_LOCKED = -12
  • TF_E_PORT_NOT_FOUND = -13

(as defined in errors.h) as well as the errors returned from the hardware abstraction layer (HAL) that is used.

Use :cpp:func`tf_hal_strerror` (defined in the HAL's header file) to get an error string for an error code.

Data returned from the device, when a getter is called, is handled via output parameters. These parameters are labeled with the ret_ prefix. The bindings will not write to an output parameter if NULL or nullptr is passed. This can be used to ignore outputs that you are not interested in.

None of the functions listed below are thread-safe. See the API bindings description for details.

Basic Functions

int tf_gps_v2_create(TF_GPSV2 *gps_v2, const char *uid_or_port_name, TF_HAL *hal)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • uid – Type: const char *
  • hal – Type: TF_HAL *
Returns:
  • e_code – Type: int

Creates the device object gps_v2 with the optional unique device ID or port name uid_or_port_name and adds it to the HAL hal:

TF_GPSV2 gps_v2;
tf_gps_v2_create(&gps_v2, NULL, &hal);

Normally uid_or_port_name can stay NULL. For more details about this see section UID or Port Name.

int tf_gps_v2_destroy(TF_GPSV2 *gps_v2)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Returns:
  • e_code – Type: int

Removes the device object gps_v2 from its HAL and destroys it. The device object cannot be used anymore afterwards.

int tf_gps_v2_get_coordinates(TF_GPSV2 *gps_v2, uint32_t *ret_latitude, char *ret_ns, uint32_t *ret_longitude, char *ret_ew)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_latitude – Type: uint32_t, Unit: 1/1000000 °, Range: [0 to 90000000]
  • ret_ns – Type: char, Range: ['N', 'S']
  • ret_longitude – Type: uint32_t, Unit: 1/1000000 °, Range: [0 to 180000000]
  • ret_ew – Type: char, Range: ['E', 'W']
Returns:
  • e_code – Type: int

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 tf_gps_v2_get_status().

int tf_gps_v2_get_status(TF_GPSV2 *gps_v2, bool *ret_has_fix, uint8_t *ret_satellites_view)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_has_fix – Type: bool
  • ret_satellites_view – Type: uint8_t, Range: [0 to 255]
Returns:
  • e_code – Type: int

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

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

int tf_gps_v2_get_altitude(TF_GPSV2 *gps_v2, int32_t *ret_altitude, int32_t *ret_geoidal_separation)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_altitude – Type: int32_t, Unit: 1 cm, Range: [-231 to 231 - 1]
  • ret_geoidal_separation – Type: int32_t, Unit: 1 cm, Range: [-231 to 231 - 1]
Returns:
  • e_code – Type: int

Returns the current altitude and corresponding geoidal separation.

This data is only valid if there is currently a fix as indicated by tf_gps_v2_get_status().

int tf_gps_v2_get_motion(TF_GPSV2 *gps_v2, uint32_t *ret_course, uint32_t *ret_speed)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_course – Type: uint32_t, Unit: 1/100 °, Range: [0 to 36000]
  • ret_speed – Type: uint32_t, Unit: 1/100 km/h, Range: [0 to 232 - 1]
Returns:
  • e_code – Type: int

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 tf_gps_v2_get_status().

int tf_gps_v2_get_date_time(TF_GPSV2 *gps_v2, uint32_t *ret_date, uint32_t *ret_time)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_date – Type: uint32_t, Range: [10100 to 311299]
  • ret_time – Type: uint32_t, Range: [0 to 235959999]
Returns:
  • e_code – Type: int

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.

int tf_gps_v2_get_satellite_system_status(TF_GPSV2 *gps_v2, uint8_t satellite_system, uint8_t *ret_satellite_numbers, uint8_t *ret_satellite_numbers_length, uint8_t *ret_fix, uint16_t *ret_pdop, uint16_t *ret_hdop, uint16_t *ret_vdop)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • satellite_system – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_satellite_numbers – Type: uint8_t *, Range: [0 to 255]
  • ret_satellite_numbers_length – Type: uint8_t
  • ret_fix – Type: uint8_t, Range: See constants
  • ret_pdop – Type: uint16_t, Unit: 1/100, Range: [0 to 216 - 1]
  • ret_hdop – Type: uint16_t, Unit: 1/100, Range: [0 to 216 - 1]
  • ret_vdop – Type: uint16_t, Unit: 1/100, Range: [0 to 216 - 1]
Returns:
  • e_code – Type: int

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:

For satellite_system:

  • TF_GPS_V2_SATELLITE_SYSTEM_GPS = 0
  • TF_GPS_V2_SATELLITE_SYSTEM_GLONASS = 1
  • TF_GPS_V2_SATELLITE_SYSTEM_GALILEO = 2

For ret_fix:

  • TF_GPS_V2_FIX_NO_FIX = 1
  • TF_GPS_V2_FIX_2D_FIX = 2
  • TF_GPS_V2_FIX_3D_FIX = 3
int tf_gps_v2_get_satellite_status(TF_GPSV2 *gps_v2, uint8_t satellite_system, uint8_t satellite_number, int16_t *ret_elevation, int16_t *ret_azimuth, int16_t *ret_snr)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • satellite_system – Type: uint8_t, Range: See constants
  • satellite_number – Type: uint8_t, Range: [1 to 32]
Output Parameters:
  • ret_elevation – Type: int16_t, Unit: 1 °, Range: [0 to 90]
  • ret_azimuth – Type: int16_t, Unit: 1 °, Range: [0 to 359]
  • ret_snr – Type: int16_t, Unit: 1 dB, Range: [0 to 99]
Returns:
  • e_code – Type: int

Returns the current elevation, azimuth and SNR 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:

For satellite_system:

  • TF_GPS_V2_SATELLITE_SYSTEM_GPS = 0
  • TF_GPS_V2_SATELLITE_SYSTEM_GLONASS = 1
  • TF_GPS_V2_SATELLITE_SYSTEM_GALILEO = 2

Advanced Functions

int tf_gps_v2_restart(TF_GPSV2 *gps_v2, uint8_t restart_type)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • restart_type – Type: uint8_t, Range: See constants
Returns:
  • e_code – Type: int

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 restart_type:

  • TF_GPS_V2_RESTART_TYPE_HOT_START = 0
  • TF_GPS_V2_RESTART_TYPE_WARM_START = 1
  • TF_GPS_V2_RESTART_TYPE_COLD_START = 2
  • TF_GPS_V2_RESTART_TYPE_FACTORY_RESET = 3
int tf_gps_v2_set_fix_led_config(TF_GPSV2 *gps_v2, uint8_t config)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • e_code – Type: int

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:

For config:

  • TF_GPS_V2_FIX_LED_CONFIG_OFF = 0
  • TF_GPS_V2_FIX_LED_CONFIG_ON = 1
  • TF_GPS_V2_FIX_LED_CONFIG_SHOW_HEARTBEAT = 2
  • TF_GPS_V2_FIX_LED_CONFIG_SHOW_FIX = 3
  • TF_GPS_V2_FIX_LED_CONFIG_SHOW_PPS = 4
int tf_gps_v2_get_fix_led_config(TF_GPSV2 *gps_v2, uint8_t *ret_config)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • e_code – Type: int

Returns the configuration as set by tf_gps_v2_set_fix_led_config()

The following constants are available for this function:

For ret_config:

  • TF_GPS_V2_FIX_LED_CONFIG_OFF = 0
  • TF_GPS_V2_FIX_LED_CONFIG_ON = 1
  • TF_GPS_V2_FIX_LED_CONFIG_SHOW_HEARTBEAT = 2
  • TF_GPS_V2_FIX_LED_CONFIG_SHOW_FIX = 3
  • TF_GPS_V2_FIX_LED_CONFIG_SHOW_PPS = 4
int tf_gps_v2_set_sbas_config(TF_GPSV2 *gps_v2, uint8_t sbas_config)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • sbas_config – Type: uint8_t, Range: See constants, Default: 0
Returns:
  • e_code – Type: int

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.

The following constants are available for this function:

For sbas_config:

  • TF_GPS_V2_SBAS_ENABLED = 0
  • TF_GPS_V2_SBAS_DISABLED = 1

New in version 2.0.2 (Plugin).

int tf_gps_v2_get_sbas_config(TF_GPSV2 *gps_v2, uint8_t *ret_sbas_config)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_sbas_config – Type: uint8_t, Range: See constants, Default: 0
Returns:
  • e_code – Type: int

Returns the SBAS configuration as set by tf_gps_v2_set_sbas_config()

The following constants are available for this function:

For ret_sbas_config:

  • TF_GPS_V2_SBAS_ENABLED = 0
  • TF_GPS_V2_SBAS_DISABLED = 1

New in version 2.0.2 (Plugin).

int tf_gps_v2_get_spitfp_error_count(TF_GPSV2 *gps_v2, uint32_t *ret_error_count_ack_checksum, uint32_t *ret_error_count_message_checksum, uint32_t *ret_error_count_frame, uint32_t *ret_error_count_overflow)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_error_count_ack_checksum – Type: uint32_t, Range: [0 to 232 - 1]
  • ret_error_count_message_checksum – Type: uint32_t, Range: [0 to 232 - 1]
  • ret_error_count_frame – Type: uint32_t, Range: [0 to 232 - 1]
  • ret_error_count_overflow – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • e_code – Type: int

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.

int tf_gps_v2_set_status_led_config(TF_GPSV2 *gps_v2, uint8_t config)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • e_code – Type: int

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:

For config:

  • TF_GPS_V2_STATUS_LED_CONFIG_OFF = 0
  • TF_GPS_V2_STATUS_LED_CONFIG_ON = 1
  • TF_GPS_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • TF_GPS_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3
int tf_gps_v2_get_status_led_config(TF_GPSV2 *gps_v2, uint8_t *ret_config)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • e_code – Type: int

Returns the configuration as set by tf_gps_v2_set_status_led_config()

The following constants are available for this function:

For ret_config:

  • TF_GPS_V2_STATUS_LED_CONFIG_OFF = 0
  • TF_GPS_V2_STATUS_LED_CONFIG_ON = 1
  • TF_GPS_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • TF_GPS_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3
int tf_gps_v2_get_chip_temperature(TF_GPSV2 *gps_v2, int16_t *ret_temperature)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_temperature – Type: int16_t, Unit: 1 °C, Range: [-215 to 215 - 1]
Returns:
  • e_code – Type: int

Returns the temperature 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.

int tf_gps_v2_reset(TF_GPSV2 *gps_v2)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Returns:
  • e_code – Type: int

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!

int tf_gps_v2_get_identity(TF_GPSV2 *gps_v2, char ret_uid[8], char ret_connected_uid[8], char *ret_position, uint8_t ret_hardware_version[3], uint8_t ret_firmware_version[3], uint16_t *ret_device_identifier)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_uid – Type: char[8]
  • ret_connected_uid – Type: char[8]
  • ret_position – Type: char, Range: ['a' to 'h', 'z']
  • ret_hardware_version – Type: uint8_t[3]
    • 0: major – Type: uint8_t, Range: [0 to 255]
    • 1: minor – Type: uint8_t, Range: [0 to 255]
    • 2: revision – Type: uint8_t, Range: [0 to 255]
  • ret_firmware_version – Type: uint8_t[3]
    • 0: major – Type: uint8_t, Range: [0 to 255]
    • 1: minor – Type: uint8_t, Range: [0 to 255]
    • 2: revision – Type: uint8_t, Range: [0 to 255]
  • ret_device_identifier – Type: uint16_t, Range: [0 to 216 - 1]
Returns:
  • e_code – Type: int

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.

Callback Configuration Functions

int tf_gps_v2_set_coordinates_callback_period(TF_GPSV2 *gps_v2, uint32_t period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Sets the period with which the Coordinates callback is triggered periodically. A value of 0 turns the callback off.

The Coordinates callback is only triggered if the coordinates changed since the last triggering.

int tf_gps_v2_get_coordinates_callback_period(TF_GPSV2 *gps_v2, uint32_t *ret_period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Returns the period as set by tf_gps_v2_set_coordinates_callback_period().

int tf_gps_v2_set_status_callback_period(TF_GPSV2 *gps_v2, uint32_t period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Sets the period with which the Status callback is triggered periodically. A value of 0 turns the callback off.

The Status callback is only triggered if the status changed since the last triggering.

int tf_gps_v2_get_status_callback_period(TF_GPSV2 *gps_v2, uint32_t *ret_period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Returns the period as set by tf_gps_v2_set_status_callback_period().

int tf_gps_v2_set_altitude_callback_period(TF_GPSV2 *gps_v2, uint32_t period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Sets the period with which the Altitude callback is triggered periodically. A value of 0 turns the callback off.

The Altitude callback is only triggered if the altitude changed since the last triggering.

int tf_gps_v2_get_altitude_callback_period(TF_GPSV2 *gps_v2, uint32_t *ret_period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Returns the period as set by tf_gps_v2_set_altitude_callback_period().

int tf_gps_v2_set_motion_callback_period(TF_GPSV2 *gps_v2, uint32_t period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Sets the period with which the Motion callback is triggered periodically. A value of 0 turns the callback off.

The Motion callback is only triggered if the motion changed since the last triggering.

int tf_gps_v2_get_motion_callback_period(TF_GPSV2 *gps_v2, uint32_t *ret_period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Returns the period as set by tf_gps_v2_set_motion_callback_period().

int tf_gps_v2_set_date_time_callback_period(TF_GPSV2 *gps_v2, uint32_t period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Sets the period with which the Date Time callback is triggered periodically. A value of 0 turns the callback off.

The Date Time callback is only triggered if the date or time changed since the last triggering.

int tf_gps_v2_get_date_time_callback_period(TF_GPSV2 *gps_v2, uint32_t *ret_period)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • e_code – Type: int

Returns the period as set by tf_gps_v2_set_date_time_callback_period().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding tf_gps_v2_register_*_callback function. The user_data passed to the registration function as well as the device that triggered the callback are passed to the registered callback handler.

Only one handler can be registered to a callback at the same time. To deregister a callback, call the tf_gps_v2_register_*_callback function with NULL as handler.

Note

Using callbacks for recurring events is preferred compared to using getters. Polling for a callback requires writing one byte only. See here Optimizing Performance.

Warning

Calling bindings function from inside a callback handler is not allowed. See here Thread safety.

int tf_gps_v2_register_pulse_per_second_callback(TF_GPSV2 *gps_v2, TF_GPSV2_PulsePerSecondHandler handler, void *user_data)
void handler(TF_GPSV2 *gps_v2, void *user_data)
Callback Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • user_data – Type: void *

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.

int tf_gps_v2_register_coordinates_callback(TF_GPSV2 *gps_v2, TF_GPSV2_CoordinatesHandler handler, void *user_data)
void handler(TF_GPSV2 *gps_v2, uint32_t latitude, char ns, uint32_t longitude, char ew, void *user_data)
Callback Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • latitude – Type: uint32_t, Unit: 1/1000000 °, Range: [0 to 90000000]
  • ns – Type: char, Range: ['N', 'S']
  • longitude – Type: uint32_t, Unit: 1/1000000 °, Range: [0 to 180000000]
  • ew – Type: char, Range: ['E', 'W']
  • user_data – Type: void *

This callback is triggered periodically with the period that is set by tf_gps_v2_set_coordinates_callback_period(). The parameters are the same as for tf_gps_v2_get_coordinates().

The Coordinates callback is only triggered if the coordinates changed since the last triggering and if there is currently a fix as indicated by tf_gps_v2_get_status().

int tf_gps_v2_register_status_callback(TF_GPSV2 *gps_v2, TF_GPSV2_StatusHandler handler, void *user_data)
void handler(TF_GPSV2 *gps_v2, bool has_fix, uint8_t satellites_view, void *user_data)
Callback Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • has_fix – Type: bool
  • satellites_view – Type: uint8_t, Range: [0 to 255]
  • user_data – Type: void *

This callback is triggered periodically with the period that is set by tf_gps_v2_set_status_callback_period(). The parameters are the same as for tf_gps_v2_get_status().

The Status callback is only triggered if the status changed since the last triggering.

int tf_gps_v2_register_altitude_callback(TF_GPSV2 *gps_v2, TF_GPSV2_AltitudeHandler handler, void *user_data)
void handler(TF_GPSV2 *gps_v2, int32_t altitude, int32_t geoidal_separation, void *user_data)
Callback Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • altitude – Type: int32_t, Unit: 1 cm, Range: [-231 to 231 - 1]
  • geoidal_separation – Type: int32_t, Unit: 1 cm, Range: [-231 to 231 - 1]
  • user_data – Type: void *

This callback is triggered periodically with the period that is set by tf_gps_v2_set_altitude_callback_period(). The parameters are the same as for tf_gps_v2_get_altitude().

The Altitude callback is only triggered if the altitude changed since the last triggering and if there is currently a fix as indicated by tf_gps_v2_get_status().

int tf_gps_v2_register_motion_callback(TF_GPSV2 *gps_v2, TF_GPSV2_MotionHandler handler, void *user_data)
void handler(TF_GPSV2 *gps_v2, uint32_t course, uint32_t speed, void *user_data)
Callback Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • course – Type: uint32_t, Unit: 1/100 °, Range: [0 to 36000]
  • speed – Type: uint32_t, Unit: 1/100 km/h, Range: [0 to 232 - 1]
  • user_data – Type: void *

This callback is triggered periodically with the period that is set by tf_gps_v2_set_motion_callback_period(). The parameters are the same as for tf_gps_v2_get_motion().

The Motion callback is only triggered if the motion changed since the last triggering and if there is currently a fix as indicated by tf_gps_v2_get_status().

int tf_gps_v2_register_date_time_callback(TF_GPSV2 *gps_v2, TF_GPSV2_DateTimeHandler handler, void *user_data)
void handler(TF_GPSV2 *gps_v2, uint32_t date, uint32_t time, void *user_data)
Callback Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • date – Type: uint32_t, Range: [10100 to 311299]
  • time – Type: uint32_t, Range: [0 to 235959999]
  • user_data – Type: void *

This callback is triggered periodically with the period that is set by tf_gps_v2_set_date_time_callback_period(). The parameters are the same as for tf_gps_v2_get_date_time().

The Date Time callback is only triggered if the date or time changed since the last triggering.

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object.

int tf_gps_v2_get_response_expected(TF_GPSV2 *gps_v2, uint8_t function_id, bool *ret_response_expected)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • function_id – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_response_expected – Type: bool
Returns:
  • e_code – Type: int

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 tf_gps_v2_set_response_expected(). 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 function_id:

  • TF_GPS_V2_FUNCTION_RESTART = 6
  • TF_GPS_V2_FUNCTION_SET_FIX_LED_CONFIG = 9
  • TF_GPS_V2_FUNCTION_SET_COORDINATES_CALLBACK_PERIOD = 11
  • TF_GPS_V2_FUNCTION_SET_STATUS_CALLBACK_PERIOD = 13
  • TF_GPS_V2_FUNCTION_SET_ALTITUDE_CALLBACK_PERIOD = 15
  • TF_GPS_V2_FUNCTION_SET_MOTION_CALLBACK_PERIOD = 17
  • TF_GPS_V2_FUNCTION_SET_DATE_TIME_CALLBACK_PERIOD = 19
  • TF_GPS_V2_FUNCTION_SET_SBAS_CONFIG = 27
  • TF_GPS_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • TF_GPS_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • TF_GPS_V2_FUNCTION_RESET = 243
  • TF_GPS_V2_FUNCTION_WRITE_UID = 248
int tf_gps_v2_set_response_expected(TF_GPSV2 *gps_v2, uint8_t function_id, bool response_expected)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • function_id – Type: uint8_t, Range: See constants
  • response_expected – Type: bool
Returns:
  • e_code – Type: int

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 function_id:

  • TF_GPS_V2_FUNCTION_RESTART = 6
  • TF_GPS_V2_FUNCTION_SET_FIX_LED_CONFIG = 9
  • TF_GPS_V2_FUNCTION_SET_COORDINATES_CALLBACK_PERIOD = 11
  • TF_GPS_V2_FUNCTION_SET_STATUS_CALLBACK_PERIOD = 13
  • TF_GPS_V2_FUNCTION_SET_ALTITUDE_CALLBACK_PERIOD = 15
  • TF_GPS_V2_FUNCTION_SET_MOTION_CALLBACK_PERIOD = 17
  • TF_GPS_V2_FUNCTION_SET_DATE_TIME_CALLBACK_PERIOD = 19
  • TF_GPS_V2_FUNCTION_SET_SBAS_CONFIG = 27
  • TF_GPS_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • TF_GPS_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • TF_GPS_V2_FUNCTION_RESET = 243
  • TF_GPS_V2_FUNCTION_WRITE_UID = 248
int tf_gps_v2_set_response_expected_all(TF_GPSV2 *gps_v2, bool response_expected)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • response_expected – Type: bool
Returns:
  • e_code – Type: int

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

Internal Functions

Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.

int tf_gps_v2_set_bootloader_mode(TF_GPSV2 *gps_v2, uint8_t mode, uint8_t *ret_status)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • mode – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_status – Type: uint8_t, Range: See constants
Returns:
  • e_code – Type: int

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:

For mode:

  • TF_GPS_V2_BOOTLOADER_MODE_BOOTLOADER = 0
  • TF_GPS_V2_BOOTLOADER_MODE_FIRMWARE = 1
  • TF_GPS_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • TF_GPS_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • TF_GPS_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For ret_status:

  • TF_GPS_V2_BOOTLOADER_STATUS_OK = 0
  • TF_GPS_V2_BOOTLOADER_STATUS_INVALID_MODE = 1
  • TF_GPS_V2_BOOTLOADER_STATUS_NO_CHANGE = 2
  • TF_GPS_V2_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • TF_GPS_V2_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • TF_GPS_V2_BOOTLOADER_STATUS_CRC_MISMATCH = 5
int tf_gps_v2_get_bootloader_mode(TF_GPSV2 *gps_v2, uint8_t *ret_mode)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_mode – Type: uint8_t, Range: See constants
Returns:
  • e_code – Type: int

Returns the current bootloader mode, see tf_gps_v2_set_bootloader_mode().

The following constants are available for this function:

For ret_mode:

  • TF_GPS_V2_BOOTLOADER_MODE_BOOTLOADER = 0
  • TF_GPS_V2_BOOTLOADER_MODE_FIRMWARE = 1
  • TF_GPS_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • TF_GPS_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • TF_GPS_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
int tf_gps_v2_set_write_firmware_pointer(TF_GPSV2 *gps_v2, uint32_t pointer)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • pointer – Type: uint32_t, Unit: 1 B, Range: [0 to 232 - 1]
Returns:
  • e_code – Type: int

Sets the firmware pointer for tf_gps_v2_write_firmware(). 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.

int tf_gps_v2_write_firmware(TF_GPSV2 *gps_v2, const uint8_t data[64], uint8_t *ret_status)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • data – Type: const uint8_t[64], Range: [0 to 255]
Output Parameters:
  • ret_status – Type: uint8_t, Range: [0 to 255]
Returns:
  • e_code – Type: int

Writes 64 Bytes of firmware at the position as written by tf_gps_v2_set_write_firmware_pointer() 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.

int tf_gps_v2_write_uid(TF_GPSV2 *gps_v2, uint32_t uid)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
  • uid – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • e_code – Type: int

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.

int tf_gps_v2_read_uid(TF_GPSV2 *gps_v2, uint32_t *ret_uid)
Parameters:
  • gps_v2 – Type: TF_GPSV2 *
Output Parameters:
  • ret_uid – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • e_code – Type: int

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

Constants

TF_GPS_V2_DEVICE_IDENTIFIER

This constant is used to identify a GPS Bricklet 2.0.

The functions tf_gps_v2_get_identity() and tf_hal_get_device_info() have a device_identifier output parameter to specify the Brick's or Bricklet's type.

TF_GPS_V2_DEVICE_DISPLAY_NAME

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