Shell - GPS Bricklet 2.0

This is the description of the Shell 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 Shell API bindings is part of their general description.

Examples

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

Simple

Download (example-simple.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your GPS Bricklet 2.0

# Get current coordinates
tinkerforge call gps-v2-bricklet $uid get-coordinates

Callback

Download (example-callback.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your GPS Bricklet 2.0

# Handle incoming coordinates callbacks
tinkerforge dispatch gps-v2-bricklet $uid coordinates &

# 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!
tinkerforge call gps-v2-bricklet $uid set-coordinates-callback-period 1000

echo "Press key to exit"; read dummy

kill -- -$$ # Stop callback dispatch in background

API

Possible exit codes for all tinkerforge commands are:

  • 1: interrupted (ctrl+c)
  • 2: syntax error
  • 21: Python 2.5 or newer is required
  • 22: Python argparse module is missing
  • 23: socket error
  • 24: other exception
  • 25: invalid placeholder in format string
  • 26: authentication error
  • 201: timeout occurred
  • 209: invalid argument value
  • 210: function is not supported
  • 211: unknown error

Command Structure

The common options of the call and dispatch commands are documented here. The specific command structure is shown below.

tinkerforge call gps-v2-bricklet [<option>..] <uid> <function> [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The call command is used to call a function of the GPS Bricklet 2.0. It can take several options:

  • --help shows help for the specific call command and exits
  • --list-functions shows a list of known functions of the GPS Bricklet 2.0 and exits
tinkerforge dispatch gps-v2-bricklet [<option>..] <uid> <callback>
Parameters:
  • <uid> -- string
  • <callback> -- string

The dispatch command is used to dispatch a callback of the GPS Bricklet 2.0. It can take several options:

  • --help shows help for the specific dispatch command and exits
  • --list-callbacks shows a list of known callbacks of the GPS Bricklet 2.0 and exits
tinkerforge call gps-v2-bricklet <uid> <function> [<option>..] [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The <function> to be called can take different options depending of its kind. All functions can take the following options:

  • --help shows help for the specific function and exits

Getter functions can take the following options:

  • --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Setter functions can take the following options:

  • --expect-response requests response and waits for it

The --expect-response option for setter functions allows to detect timeouts and other error conditions calls of setters as well. The device will then send a response for this purpose. If this option is not given for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

tinkerforge dispatch gps-v2-bricklet <uid> <callback> [<option>..]
Parameters:
  • <uid> -- string
  • <callback> -- string

The <callback> to be dispatched can take several options:

  • --help shows help for the specific callback and exits
  • --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Basic Functions

tinkerforge call gps-v2-bricklet <uid> get-coordinates
Output:
  • latitude -- int
  • ns -- char
  • longitude -- int
  • ew -- char

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 get-status.

tinkerforge call gps-v2-bricklet <uid> get-status
Output:
  • has-fix -- bool
  • satellites-view -- int

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.

tinkerforge call gps-v2-bricklet <uid> get-altitude
Output:
  • altitude -- int
  • geoidal-separation -- int

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 get-status.

tinkerforge call gps-v2-bricklet <uid> get-motion
Output:
  • course -- int
  • speed -- int

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 get-status.

tinkerforge call gps-v2-bricklet <uid> get-date-time
Output:
  • date -- int
  • time -- 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 14.05.13 as date and 195923568 means 19:59:23.568 as time.

tinkerforge call gps-v2-bricklet <uid> get-satellite-system-status-low-level <satellite-system>
Parameters:
  • <satellite-system> -- int (has symbols)
Output:
  • satellite-numbers-length -- int
  • satellite-numbers-data -- int,int,..9x..,int
  • fix -- int (has symbols)
  • pdop -- int
  • hdop -- int
  • vdop -- 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 symbols are available for this function:

  • satellite-system-gps = 0, for <satellite-system>
  • satellite-system-glonass = 1, for <satellite-system>
  • satellite-system-galileo = 2, for <satellite-system>
  • fix-no-fix = 1, for fix
  • fix-2d-fix = 2, for fix
  • fix-3d-fix = 3, for fix
tinkerforge call gps-v2-bricklet <uid> get-satellite-status <satellite-system> <satellite-number>
Parameters:
  • <satellite-system> -- int (has symbols)
  • <satellite-number> -- int
Output:
  • elevation -- int
  • azimuth -- int
  • snr -- int

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 symbols are available for this function:

  • satellite-system-gps = 0, for <satellite-system>
  • satellite-system-glonass = 1, for <satellite-system>
  • satellite-system-galileo = 2, for <satellite-system>

Advanced Functions

tinkerforge call gps-v2-bricklet <uid> restart <restart-type>
Parameters:
  • <restart-type> -- int (has symbols)
Output:

no output

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 symbols are available for this function:

  • restart-type-hot-start = 0, for <restart-type>
  • restart-type-warm-start = 1, for <restart-type>
  • restart-type-cold-start = 2, for <restart-type>
  • restart-type-factory-reset = 3, for <restart-type>
tinkerforge call gps-v2-bricklet <uid> set-fix-led-config <config>
Parameters:
  • <config> -- int (has symbols)
Output:

no output

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 symbols are available for this function:

  • fix-led-config-off = 0, for <config>
  • fix-led-config-on = 1, for <config>
  • fix-led-config-show-heartbeat = 2, for <config>
  • fix-led-config-show-fix = 3, for <config>
  • fix-led-config-show-pps = 4, for <config>
tinkerforge call gps-v2-bricklet <uid> get-fix-led-config
Output:
  • config -- int (has symbols)

Returns the configuration as set by set-fix-led-config

The following symbols are available for this function:

  • fix-led-config-off = 0, for config
  • fix-led-config-on = 1, for config
  • fix-led-config-show-heartbeat = 2, for config
  • fix-led-config-show-fix = 3, for config
  • fix-led-config-show-pps = 4, for config
tinkerforge call gps-v2-bricklet <uid> set-sbas-config <sbas-config>
Parameters:
  • <sbas-config> -- int (has symbols)
Output:

no output

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 symbols are available for this function:

  • sbas-enabled = 0, for <sbas-config>
  • sbas-disabled = 1, for <sbas-config>

New in version 2.0.2 (Plugin).

tinkerforge call gps-v2-bricklet <uid> get-sbas-config
Output:
  • sbas-config -- int (has symbols)

Returns the SBAS configuration as set by set-sbas-config

The following symbols are available for this function:

  • sbas-enabled = 0, for sbas-config
  • sbas-disabled = 1, for sbas-config

New in version 2.0.2 (Plugin).

tinkerforge call gps-v2-bricklet <uid> get-spitfp-error-count
Output:
  • error-count-ack-checksum -- int
  • error-count-message-checksum -- int
  • error-count-frame -- int
  • error-count-overflow -- 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.

tinkerforge call gps-v2-bricklet <uid> set-bootloader-mode <mode>
Parameters:
  • <mode> -- int (has symbols)
Output:
  • status -- int (has symbols)

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 symbols are available for this function:

  • bootloader-mode-bootloader = 0, for <mode>
  • bootloader-mode-firmware = 1, for <mode>
  • bootloader-mode-bootloader-wait-for-reboot = 2, for <mode>
  • bootloader-mode-firmware-wait-for-reboot = 3, for <mode>
  • bootloader-mode-firmware-wait-for-erase-and-reboot = 4, for <mode>
  • bootloader-status-ok = 0, for status
  • bootloader-status-invalid-mode = 1, for status
  • bootloader-status-no-change = 2, for status
  • bootloader-status-entry-function-not-present = 3, for status
  • bootloader-status-device-identifier-incorrect = 4, for status
  • bootloader-status-crc-mismatch = 5, for status
tinkerforge call gps-v2-bricklet <uid> get-bootloader-mode
Output:
  • mode -- int (has symbols)

Returns the current bootloader mode, see set-bootloader-mode.

The following symbols are available for this function:

  • bootloader-mode-bootloader = 0, for mode
  • bootloader-mode-firmware = 1, for mode
  • bootloader-mode-bootloader-wait-for-reboot = 2, for mode
  • bootloader-mode-firmware-wait-for-reboot = 3, for mode
  • bootloader-mode-firmware-wait-for-erase-and-reboot = 4, for mode
tinkerforge call gps-v2-bricklet <uid> set-write-firmware-pointer <pointer>
Parameters:
  • <pointer> -- int
Output:

no output

Sets the firmware pointer for 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.

tinkerforge call gps-v2-bricklet <uid> write-firmware <data>
Parameters:
  • <data> -- int,int,..61x..,int
Output:
  • status -- int

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

tinkerforge call gps-v2-bricklet <uid> set-status-led-config <config>
Parameters:
  • <config> -- int (has symbols)
Output:

no output

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 symbols are available for this function:

  • status-led-config-off = 0, for <config>
  • status-led-config-on = 1, for <config>
  • status-led-config-show-heartbeat = 2, for <config>
  • status-led-config-show-status = 3, for <config>
tinkerforge call gps-v2-bricklet <uid> get-status-led-config
Output:
  • config -- int (has symbols)

Returns the configuration as set by set-status-led-config

The following symbols are available for this function:

  • status-led-config-off = 0, for config
  • status-led-config-on = 1, for config
  • status-led-config-show-heartbeat = 2, for config
  • status-led-config-show-status = 3, for config
tinkerforge call gps-v2-bricklet <uid> get-chip-temperature
Output:
  • temperature -- int

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.

tinkerforge call gps-v2-bricklet <uid> reset
Output:no output

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!

tinkerforge call gps-v2-bricklet <uid> write-uid <uid>
Parameters:
  • <uid> -- int
Output:

no output

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.

tinkerforge call gps-v2-bricklet <uid> read-uid
Output:
  • uid -- int

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

tinkerforge call gps-v2-bricklet <uid> get-identity
Output:
  • uid -- string
  • connected-uid -- string
  • position -- char
  • hardware-version -- int,int,int
  • firmware-version -- int,int,int
  • device-identifier -- int (has symbols)

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

Callback Configuration Functions

tinkerforge call gps-v2-bricklet <uid> set-coordinates-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms 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.

The default value is 0.

tinkerforge call gps-v2-bricklet <uid> get-coordinates-callback-period
Output:
  • period -- int

Returns the period as set by set-coordinates-callback-period.

tinkerforge call gps-v2-bricklet <uid> set-status-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms 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.

The default value is 0.

tinkerforge call gps-v2-bricklet <uid> get-status-callback-period
Output:
  • period -- int

Returns the period as set by set-status-callback-period.

tinkerforge call gps-v2-bricklet <uid> set-altitude-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms 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.

The default value is 0.

tinkerforge call gps-v2-bricklet <uid> get-altitude-callback-period
Output:
  • period -- int

Returns the period as set by set-altitude-callback-period.

tinkerforge call gps-v2-bricklet <uid> set-motion-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms 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.

The default value is 0.

tinkerforge call gps-v2-bricklet <uid> get-motion-callback-period
Output:
  • period -- int

Returns the period as set by set-motion-callback-period.

tinkerforge call gps-v2-bricklet <uid> set-date-time-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms 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.

The default value is 0.

tinkerforge call gps-v2-bricklet <uid> get-date-time-callback-period
Output:
  • period -- int

Returns the period as set by set-date-time-callback-period.

Callbacks

Callbacks can be used to receive time critical or recurring data from the device:

tinkerforge dispatch gps-v2-bricklet <uid> example

The available callbacks 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.

tinkerforge dispatch gps-v2-bricklet <uid> pulse-per-second
Output:no output

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.

tinkerforge dispatch gps-v2-bricklet <uid> coordinates
Output:
  • latitude -- int
  • ns -- char
  • longitude -- int
  • ew -- char

This callback is triggered periodically with the period that is set by set-coordinates-callback-period. The parameters are the same as for 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 get-status.

tinkerforge dispatch gps-v2-bricklet <uid> status
Output:
  • has-fix -- bool
  • satellites-view -- int

This callback is triggered periodically with the period that is set by set-status-callback-period. The parameters are the same as for get-status.

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

tinkerforge dispatch gps-v2-bricklet <uid> altitude
Output:
  • altitude -- int
  • geoidal-separation -- int

This callback is triggered periodically with the period that is set by set-altitude-callback-period. The parameters are the same as for 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 get-status.

tinkerforge dispatch gps-v2-bricklet <uid> motion
Output:
  • course -- int
  • speed -- int

This callback is triggered periodically with the period that is set by set-motion-callback-period. The parameters are the same as for 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 get-status.

tinkerforge dispatch gps-v2-bricklet <uid> date-time
Output:
  • date -- int
  • time -- int

This callback is triggered periodically with the period that is set by set-date-time-callback-period. The parameters are the same as for get-date-time.

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