class Tinkerforge::BrickletCompass

3-axis compass with 10 nanotesla and 0.1° resolution

Constants

CALLBACK_HEADING

This callback is triggered periodically according to the configuration set by BrickletCompass#set_heading_callback_configuration.

The parameter is the same as BrickletCompass#get_heading.

CALLBACK_MAGNETIC_FLUX_DENSITY

This callback is triggered periodically according to the configuration set by BrickletCompass#set_magnetic_flux_density_callback_configuration.

The parameters are the same as BrickletCompass#get_magnetic_flux_density.

Public Class Methods

new(uid, ipcon) click to toggle source

Creates an object with the unique device ID uid and adds it to the IP Connection ipcon.

Calls superclass method
# File lib/tinkerforge/bricklet_compass.rb, line 81
def initialize(uid, ipcon)
  super uid, ipcon, DEVICE_IDENTIFIER, DEVICE_DISPLAY_NAME

  @api_version = [2, 0, 0]

  @response_expected[FUNCTION_GET_HEADING] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_HEADING_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_HEADING_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_MAGNETIC_FLUX_DENSITY] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_MAGNETIC_FLUX_DENSITY_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_MAGNETIC_FLUX_DENSITY_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_CONFIGURATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_CALIBRATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_CALIBRATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_SPITFP_ERROR_COUNT] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_BOOTLOADER_MODE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_BOOTLOADER_MODE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_WRITE_FIRMWARE_POINTER] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_WRITE_FIRMWARE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_STATUS_LED_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_STATUS_LED_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_CHIP_TEMPERATURE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_RESET] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_WRITE_UID] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_READ_UID] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IDENTITY] = RESPONSE_EXPECTED_ALWAYS_TRUE

  @callback_formats[CALLBACK_HEADING] = [10, 's']
  @callback_formats[CALLBACK_MAGNETIC_FLUX_DENSITY] = [20, 'l l l']

  @ipcon.add_device self
end

Public Instance Methods

get_bootloader_mode() click to toggle source

Returns the current bootloader mode, see BrickletCompass#set_bootloader_mode.

# File lib/tinkerforge/bricklet_compass.rb, line 281
def get_bootloader_mode
  check_validity

  send_request FUNCTION_GET_BOOTLOADER_MODE, [], '', 9, 'C'
end
get_calibration() click to toggle source

Returns the calibration parameters as set by BrickletCompass#set_calibration.

# File lib/tinkerforge/bricklet_compass.rb, line 242
def get_calibration
  check_validity

  send_request FUNCTION_GET_CALIBRATION, [], '', 20, 's3 s3'
end
get_chip_temperature() click to toggle source

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.

# File lib/tinkerforge/bricklet_compass.rb, line 339
def get_chip_temperature
  check_validity

  send_request FUNCTION_GET_CHIP_TEMPERATURE, [], '', 10, 's'
end
get_configuration() click to toggle source

Returns the configuration as set by BrickletCompass#set_configuration.

# File lib/tinkerforge/bricklet_compass.rb, line 222
def get_configuration
  check_validity

  send_request FUNCTION_GET_CONFIGURATION, [], '', 10, 'C ?'
end
get_heading() click to toggle source

Returns the heading (north = 0 degree, east = 90 degree).

Alternatively you can use BrickletCompass#get_magnetic_flux_density and calculate the heading with “heading = atan2(y, x) * 180 / PI“.

If you want to get the value periodically, it is recommended to use the CALLBACK_HEADING callback. You can set the callback configuration with BrickletCompass#set_heading_callback_configuration.

# File lib/tinkerforge/bricklet_compass.rb, line 124
def get_heading
  check_validity

  send_request FUNCTION_GET_HEADING, [], '', 10, 's'
end
get_heading_callback_configuration() click to toggle source

Returns the callback configuration as set by BrickletCompass#set_heading_callback_configuration.

# File lib/tinkerforge/bricklet_compass.rb, line 162
def get_heading_callback_configuration
  check_validity

  send_request FUNCTION_GET_HEADING_CALLBACK_CONFIGURATION, [], '', 18, 'L ? k s s'
end
get_identity() click to toggle source

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 :ref:`Isolator Bricklet <isolator_bricklet>` is always at position 'z'.

The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|

# File lib/tinkerforge/bricklet_compass.rb, line 386
def get_identity
  send_request FUNCTION_GET_IDENTITY, [], '', 33, 'Z8 Z8 k C3 C3 S'
end
get_magnetic_flux_density() click to toggle source

Returns the `magnetic flux density (magnetic induction) <CALLBACK_MAGNETIC_FLUX_DENSITY callback. You can set the callback configuration with BrickletCompass#set_magnetic_flux_density_callback_configuration.

# File lib/tinkerforge/bricklet_compass.rb, line 174
def get_magnetic_flux_density
  check_validity

  send_request FUNCTION_GET_MAGNETIC_FLUX_DENSITY, [], '', 20, 'l l l'
end
get_magnetic_flux_density_callback_configuration() click to toggle source

Returns the callback configuration as set by BrickletCompass#set_magnetic_flux_density_callback_configuration.

# File lib/tinkerforge/bricklet_compass.rb, line 197
def get_magnetic_flux_density_callback_configuration
  check_validity

  send_request FUNCTION_GET_MAGNETIC_FLUX_DENSITY_CALLBACK_CONFIGURATION, [], '', 13, 'L ?'
end
get_spitfp_error_count() click to toggle source

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.

# File lib/tinkerforge/bricklet_compass.rb, line 259
def get_spitfp_error_count
  check_validity

  send_request FUNCTION_GET_SPITFP_ERROR_COUNT, [], '', 24, 'L L L L'
end
get_status_led_config() click to toggle source

Returns the configuration as set by BrickletCompass#set_status_led_config

# File lib/tinkerforge/bricklet_compass.rb, line 327
def get_status_led_config
  check_validity

  send_request FUNCTION_GET_STATUS_LED_CONFIG, [], '', 9, 'C'
end
read_uid() click to toggle source

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

# File lib/tinkerforge/bricklet_compass.rb, line 370
def read_uid
  check_validity

  send_request FUNCTION_READ_UID, [], '', 12, 'L'
end
register_callback(id, &block) click to toggle source

Registers a callback with ID id to the block block.

# File lib/tinkerforge/bricklet_compass.rb, line 391
def register_callback(id, &block)
  callback = block
  @registered_callbacks[id] = callback
end
reset() click to toggle source

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!

# File lib/tinkerforge/bricklet_compass.rb, line 351
def reset
  check_validity

  send_request FUNCTION_RESET, [], '', 8, ''
end
set_bootloader_mode(mode) click to toggle source

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.

# File lib/tinkerforge/bricklet_compass.rb, line 274
def set_bootloader_mode(mode)
  check_validity

  send_request FUNCTION_SET_BOOTLOADER_MODE, [mode], 'C', 9, 'C'
end
set_calibration(offset, gain) click to toggle source

Sets offset and gain for each of the three axes.

The Bricklet is factory calibrated. If you want to re-calibrate the Bricklet we recommend that you do the calibration through Brick Viewer.

The calibration is saved in non-volatile memory and only has to be done once.

# File lib/tinkerforge/bricklet_compass.rb, line 235
def set_calibration(offset, gain)
  check_validity

  send_request FUNCTION_SET_CALIBRATION, [offset, gain], 's3 s3', 8, ''
end
set_configuration(data_rate, background_calibration) click to toggle source

Configures the data rate and background calibration.

  • Data Rate: Sets the data rate that is used by the magnetometer. The lower the data rate, the lower is the noise on the data.

  • Background Calibration: Set to true to enable the background calibration and false to turn it off. If the background calibration is enabled the sensing polarity is flipped once per second to automatically calculate and remove offset that is caused by temperature changes. This polarity flipping takes about 20ms. This means that once a second you will not get new data for a period of 20ms. We highly recommend that you keep the background calibration enabled and only disable it if the 20ms off-time is a problem in your application.

# File lib/tinkerforge/bricklet_compass.rb, line 215
def set_configuration(data_rate, background_calibration)
  check_validity

  send_request FUNCTION_SET_CONFIGURATION, [data_rate, background_calibration], 'C ?', 8, ''
end
set_heading_callback_configuration(period, value_has_to_change, option, min, max) click to toggle source

The period is the period with which the CALLBACK_HEADING callback is triggered periodically. A value of 0 turns the callback off.

If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The `option`-parameter together with min/max sets a threshold for the CALLBACK_HEADING callback.

The following options are possible:

"Option", "Description"

"'x'",    "Threshold is turned off"
"'o'",    "Threshold is triggered when the value is *outside* the min and max values"
"'i'",    "Threshold is triggered when the value is *inside* or equal to the min and max values"
"'<'",    "Threshold is triggered when the value is smaller than the min value (max is ignored)"
"'>'",    "Threshold is triggered when the value is greater than the min value (max is ignored)"

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

# File lib/tinkerforge/bricklet_compass.rb, line 155
def set_heading_callback_configuration(period, value_has_to_change, option, min, max)
  check_validity

  send_request FUNCTION_SET_HEADING_CALLBACK_CONFIGURATION, [period, value_has_to_change, option, min, max], 'L ? k s s', 8, ''
end
set_magnetic_flux_density_callback_configuration(period, value_has_to_change) click to toggle source

The period is the period with which the CALLBACK_MAGNETIC_FLUX_DENSITY callback is triggered periodically. A value of 0 turns the callback off.

If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

# File lib/tinkerforge/bricklet_compass.rb, line 189
def set_magnetic_flux_density_callback_configuration(period, value_has_to_change)
  check_validity

  send_request FUNCTION_SET_MAGNETIC_FLUX_DENSITY_CALLBACK_CONFIGURATION, [period, value_has_to_change], 'L ?', 8, ''
end
set_status_led_config(config) click to toggle source

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.

# File lib/tinkerforge/bricklet_compass.rb, line 320
def set_status_led_config(config)
  check_validity

  send_request FUNCTION_SET_STATUS_LED_CONFIG, [config], 'C', 8, ''
end
set_write_firmware_pointer(pointer) click to toggle source

Sets the firmware pointer for BrickletCompass#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.

# File lib/tinkerforge/bricklet_compass.rb, line 293
def set_write_firmware_pointer(pointer)
  check_validity

  send_request FUNCTION_SET_WRITE_FIRMWARE_POINTER, [pointer], 'L', 8, ''
end
write_firmware(data) click to toggle source

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

# File lib/tinkerforge/bricklet_compass.rb, line 307
def write_firmware(data)
  check_validity

  send_request FUNCTION_WRITE_FIRMWARE, [data], 'C64', 9, 'C'
end
write_uid(uid) click to toggle source

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.

# File lib/tinkerforge/bricklet_compass.rb, line 362
def write_uid(uid)
  check_validity

  send_request FUNCTION_WRITE_UID, [uid], 'L', 8, ''
end