This is the description of the Ruby 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 Ruby 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 | #!/usr/bin/env ruby
# -*- ruby encoding: utf-8 -*-
require 'tinkerforge/ip_connection'
require 'tinkerforge/bricklet_gps'
include Tinkerforge
HOST = 'localhost'
PORT = 4223
UID = 'XYZ' # Change XYZ to the UID of your GPS Bricklet
ipcon = IPConnection.new # Create IP connection
gps = BrickletGPS.new UID, ipcon # Create device object
ipcon.connect HOST, PORT # Connect to brickd
# Don't use device before ipcon is connected
# Get current coordinates as [latitude, ns, longitude, ew, pdop, hdop, vdop, epe]
coordinates = gps.get_coordinates
puts "Latitude: #{coordinates[0]/1000000.0} °"
puts "N/S: #{coordinates[1]}"
puts "Longitude: #{coordinates[2]/1000000.0} °"
puts "E/W: #{coordinates[3]}"
puts 'Press key to exit'
$stdin.gets
ipcon.disconnect
|
Download (example_callback.rb)
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 | #!/usr/bin/env ruby
# -*- ruby encoding: utf-8 -*-
require 'tinkerforge/ip_connection'
require 'tinkerforge/bricklet_gps'
include Tinkerforge
HOST = 'localhost'
PORT = 4223
UID = 'XYZ' # Change XYZ to the UID of your GPS Bricklet
ipcon = IPConnection.new # Create IP connection
gps = BrickletGPS.new UID, ipcon # Create device object
ipcon.connect HOST, PORT # Connect to brickd
# Don't use device before ipcon is connected
# Register coordinates callback
gps.register_callback(BrickletGPS::CALLBACK_COORDINATES) do |latitude, ns, longitude, ew,
pdop, hdop, vdop, epe|
puts "Latitude: #{latitude/1000000.0} °"
puts "N/S: #{ns}"
puts "Longitude: #{longitude/1000000.0} °"
puts "E/W: #{ew}"
puts ''
end
# 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.set_coordinates_callback_period 1000
puts 'Press key to exit'
$stdin.gets
ipcon.disconnect
|
All functions listed below are thread-safe.
BrickletGPS
::
new
(uid, ipcon) → gps¶Parameters: |
|
---|---|
Returns: |
|
Creates an object with the unique device ID uid
:
gps = BrickletGPS.new 'YOUR_DEVICE_UID', ipcon
This object can then be used after the IP Connection is connected.
BrickletGPS
#
get_coordinates
→ [int, chr, int, chr, int, int, int, int]¶Return Array: |
|
---|
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
#get_status
.
BrickletGPS
#
get_status
→ [int, int, int]¶Return Array: |
|
---|
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, #get_coordinates , #get_altitude and #get_motion return invalid data |
2 | 2D Fix, only #get_coordinates and #get_motion return valid data |
3 | 3D Fix, #get_coordinates , #get_altitude and #get_motion 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
#
get_altitude
→ [int, int]¶Return Array: |
|
---|
Returns the current altitude and corresponding geoidal separation.
This data is only valid if there is currently a fix as indicated by
#get_status
.
BrickletGPS
#
get_motion
→ [int, int]¶Return Array: |
|
---|
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
#get_status
.
BrickletGPS
#
get_date_time
→ [int, int]¶Return Array: |
|
---|
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
(restart_type) → nil¶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 restart_type:
BrickletGPS
#
get_identity
→ [str, str, chr, [int, ...], [int, ...], int]¶Return Array: |
|
---|
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
#
register_callback
(callback_id) { |param [, ...]| block } → nil¶Parameters: |
|
---|
Registers the given block
with the given callback_id
.
The available callback IDs with corresponding function signatures are listed below.
BrickletGPS
#
set_coordinates_callback_period
(period) → nil¶Parameters: |
|
---|
Sets the period with which the ::CALLBACK_COORDINATES
callback is triggered
periodically. A value of 0 turns the callback off.
The ::CALLBACK_COORDINATES
callback is only triggered if the coordinates changed
since the last triggering.
BrickletGPS
#
get_coordinates_callback_period
→ int¶Returns: |
|
---|
Returns the period as set by #set_coordinates_callback_period
.
BrickletGPS
#
set_status_callback_period
(period) → nil¶Parameters: |
|
---|
Sets the period with which the ::CALLBACK_STATUS
callback is triggered
periodically. A value of 0 turns the callback off.
The ::CALLBACK_STATUS
callback is only triggered if the status changed since the
last triggering.
BrickletGPS
#
get_status_callback_period
→ int¶Returns: |
|
---|
Returns the period as set by #set_status_callback_period
.
BrickletGPS
#
set_altitude_callback_period
(period) → nil¶Parameters: |
|
---|
Sets the period with which the ::CALLBACK_ALTITUDE
callback is triggered
periodically. A value of 0 turns the callback off.
The ::CALLBACK_ALTITUDE
callback is only triggered if the altitude changed since
the last triggering.
BrickletGPS
#
get_altitude_callback_period
→ int¶Returns: |
|
---|
Returns the period as set by #set_altitude_callback_period
.
BrickletGPS
#
set_motion_callback_period
(period) → nil¶Parameters: |
|
---|
Sets the period with which the ::CALLBACK_MOTION
callback is triggered
periodically. A value of 0 turns the callback off.
The ::CALLBACK_MOTION
callback is only triggered if the motion changed since the
last triggering.
BrickletGPS
#
get_motion_callback_period
→ int¶Returns: |
|
---|
Returns the period as set by #set_motion_callback_period
.
BrickletGPS
#
set_date_time_callback_period
(period) → nil¶Parameters: |
|
---|
Sets the period with which the ::CALLBACK_DATE_TIME
callback is triggered
periodically. A value of 0 turns the callback off.
The ::CALLBACK_DATE_TIME
callback is only triggered if the date or time changed
since the last triggering.
BrickletGPS
#
get_date_time_callback_period
→ int¶Returns: |
|
---|
Returns the period as set by #set_date_time_callback_period
.
Callbacks can be registered to receive time critical or recurring data from
the device. The registration is done with the
#register_callback
function of
the device object. The first parameter is the callback ID and the second
parameter is a block:
gps.register_callback BrickletGPS::CALLBACK_EXAMPLE, do |param|
puts "#{param}"
end
The available constants with inherent number and 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
::
CALLBACK_COORDINATES
¶Callback Parameters: |
|
---|
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 ::CALLBACK_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
.
BrickletGPS
::
CALLBACK_STATUS
¶Callback Parameters: |
|
---|
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 ::CALLBACK_STATUS
callback is only triggered if the status changed since the
last triggering.
The following constants are available for this function:
For fix:
BrickletGPS
::
CALLBACK_ALTITUDE
¶Callback Parameters: |
|
---|
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 ::CALLBACK_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
.
BrickletGPS
::
CALLBACK_MOTION
¶Callback Parameters: |
|
---|
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 ::CALLBACK_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
.
BrickletGPS
::
CALLBACK_DATE_TIME
¶Callback Parameters: |
|
---|
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 ::CALLBACK_DATE_TIME
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
#
get_api_version
→ [int, ...]¶Return Array: |
|
---|
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
#
get_response_expected
(function_id) → bool¶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
#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:
BrickletGPS
#
set_response_expected
(function_id, response_expected) → nil¶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 function_id:
BrickletGPS
#
set_response_expected_all
(response_expected) → nil¶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 #get_identity()
function and the
IPConnection::CALLBACK_ENUMERATE
callback of the IP Connection have a device_identifier
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.