Class: Tinkerforge::BrickletLoadCellV2

Inherits:
Device
  • Object
show all
Defined in:
lib/tinkerforge/bricklet_load_cell_v2.rb

Overview

Measures weight with a load cell

Constant Summary collapse

DEVICE_IDENTIFIER =

:nodoc:

2104
DEVICE_DISPLAY_NAME =

:nodoc:

'Load Cell Bricklet 2.0'
CALLBACK_WEIGHT =

This callback is triggered periodically according to the configuration set by BrickletLoadCellV2#set_weight_callback_configuration.

The parameter is the same as BrickletLoadCellV2#get_weight.

4
FUNCTION_GET_WEIGHT =

:nodoc:

1
FUNCTION_SET_WEIGHT_CALLBACK_CONFIGURATION =

:nodoc:

2
FUNCTION_GET_WEIGHT_CALLBACK_CONFIGURATION =

:nodoc:

3
FUNCTION_SET_MOVING_AVERAGE =

:nodoc:

5
FUNCTION_GET_MOVING_AVERAGE =

:nodoc:

6
FUNCTION_SET_INFO_LED_CONFIG =

:nodoc:

7
FUNCTION_GET_INFO_LED_CONFIG =

:nodoc:

8
FUNCTION_CALIBRATE =

:nodoc:

9
FUNCTION_TARE =

:nodoc:

10
FUNCTION_SET_CONFIGURATION =

:nodoc:

11
FUNCTION_GET_CONFIGURATION =

:nodoc:

12
FUNCTION_GET_SPITFP_ERROR_COUNT =

:nodoc:

234
FUNCTION_SET_BOOTLOADER_MODE =

:nodoc:

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FUNCTION_GET_BOOTLOADER_MODE =

:nodoc:

236
FUNCTION_SET_WRITE_FIRMWARE_POINTER =

:nodoc:

237
FUNCTION_WRITE_FIRMWARE =

:nodoc:

238
FUNCTION_SET_STATUS_LED_CONFIG =

:nodoc:

239
FUNCTION_GET_STATUS_LED_CONFIG =

:nodoc:

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FUNCTION_GET_CHIP_TEMPERATURE =

:nodoc:

242
FUNCTION_RESET =

:nodoc:

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FUNCTION_WRITE_UID =

:nodoc:

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FUNCTION_READ_UID =

:nodoc:

249
FUNCTION_GET_IDENTITY =

:nodoc:

255
THRESHOLD_OPTION_OFF =

:nodoc:

'x'
THRESHOLD_OPTION_OUTSIDE =

:nodoc:

'o'
THRESHOLD_OPTION_INSIDE =

:nodoc:

'i'
THRESHOLD_OPTION_SMALLER =

:nodoc:

'<'
THRESHOLD_OPTION_GREATER =

:nodoc:

'>'
INFO_LED_CONFIG_OFF =

:nodoc:

0
INFO_LED_CONFIG_ON =

:nodoc:

1
INFO_LED_CONFIG_SHOW_HEARTBEAT =

:nodoc:

2
RATE_10HZ =

:nodoc:

0
RATE_80HZ =

:nodoc:

1
GAIN_128X =

:nodoc:

0
GAIN_64X =

:nodoc:

1
GAIN_32X =

:nodoc:

2
BOOTLOADER_MODE_BOOTLOADER =

:nodoc:

0
BOOTLOADER_MODE_FIRMWARE =

:nodoc:

1
BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT =

:nodoc:

2
BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT =

:nodoc:

3
BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT =

:nodoc:

4
BOOTLOADER_STATUS_OK =

:nodoc:

0
BOOTLOADER_STATUS_INVALID_MODE =

:nodoc:

1
BOOTLOADER_STATUS_NO_CHANGE =

:nodoc:

2
BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT =

:nodoc:

3
BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT =

:nodoc:

4
BOOTLOADER_STATUS_CRC_MISMATCH =

:nodoc:

5
STATUS_LED_CONFIG_OFF =

:nodoc:

0
STATUS_LED_CONFIG_ON =

:nodoc:

1
STATUS_LED_CONFIG_SHOW_HEARTBEAT =

:nodoc:

2
STATUS_LED_CONFIG_SHOW_STATUS =

:nodoc:

3

Constants inherited from Device

Device::DEVICE_IDENTIFIER_CHECK_MATCH, Device::DEVICE_IDENTIFIER_CHECK_MISMATCH, Device::DEVICE_IDENTIFIER_CHECK_PENDING, Device::RESPONSE_EXPECTED_ALWAYS_TRUE, Device::RESPONSE_EXPECTED_FALSE, Device::RESPONSE_EXPECTED_INVALID_FUNCTION_ID, Device::RESPONSE_EXPECTED_TRUE

Instance Attribute Summary

Attributes inherited from Device

#callback_formats, #expected_response_function_id, #expected_response_sequence_number, #high_level_callbacks, #registered_callbacks, #replaced, #uid

Instance Method Summary collapse

Methods inherited from Device

#check_validity, #dequeue_response, #enqueue_response, #get_api_version, #get_response_expected, #send_request, #set_response_expected, #set_response_expected_all

Constructor Details

#initialize(uid, ipcon) ⇒ BrickletLoadCellV2

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



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 81

def initialize(uid, ipcon)
  super uid, ipcon, DEVICE_IDENTIFIER, DEVICE_DISPLAY_NAME

  @api_version = [2, 0, 0]

  @response_expected[FUNCTION_GET_WEIGHT] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_WEIGHT_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_WEIGHT_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_MOVING_AVERAGE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_MOVING_AVERAGE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_INFO_LED_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_INFO_LED_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_CALIBRATE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_TARE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_SET_CONFIGURATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_CONFIGURATION] = 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_WEIGHT] = [12, 'l']

  @ipcon.add_device self
end

Instance Method Details

#calibrate(weight) ⇒ Object

To calibrate your Load Cell Bricklet 2.0 you have to

  • empty the scale and call this function with 0 and

  • add a known weight to the scale and call this function with the weight.

The calibration is saved in the flash of the Bricklet and only needs to be done once.

We recommend to use the Brick Viewer for calibration, you don’t need to call this function in your source code.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 208

def calibrate(weight)
  check_validity

  send_request FUNCTION_CALIBRATE, [weight], 'L', 8, ''
end

#get_bootloader_mode ⇒ Object

Returns the current bootloader mode, see BrickletLoadCellV2#set_bootloader_mode.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 279

def get_bootloader_mode
  check_validity

  send_request FUNCTION_GET_BOOTLOADER_MODE, [], '', 9, 'C'
end

#get_chip_temperature ⇒ Object

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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 337

def get_chip_temperature
  check_validity

  send_request FUNCTION_GET_CHIP_TEMPERATURE, [], '', 10, 's'
end

#get_configuration ⇒ Object

Returns the configuration as set by BrickletLoadCellV2#set_configuration.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 240

def get_configuration
  check_validity

  send_request FUNCTION_GET_CONFIGURATION, [], '', 10, 'C C'
end

#get_identity ⇒ Object

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|



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 384

def get_identity
  send_request FUNCTION_GET_IDENTITY, [], '', 33, 'Z8 Z8 k C3 C3 S'
end

#get_info_led_config ⇒ Object

Returns the LED configuration as set by BrickletLoadCellV2#set_info_led_config



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 192

def get_info_led_config
  check_validity

  send_request FUNCTION_GET_INFO_LED_CONFIG, [], '', 9, 'C'
end

#get_moving_average ⇒ Object

Returns the length moving average as set by BrickletLoadCellV2#set_moving_average.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 177

def get_moving_average
  check_validity

  send_request FUNCTION_GET_MOVING_AVERAGE, [], '', 10, 'S'
end

#get_spitfp_error_count ⇒ Object

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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 257

def get_spitfp_error_count
  check_validity

  send_request FUNCTION_GET_SPITFP_ERROR_COUNT, [], '', 24, 'L L L L'
end

#get_status_led_config ⇒ Object

Returns the configuration as set by BrickletLoadCellV2#set_status_led_config



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 325

def get_status_led_config
  check_validity

  send_request FUNCTION_GET_STATUS_LED_CONFIG, [], '', 9, 'C'
end

#get_weight ⇒ Object

Returns the currently measured weight.

If you want to get the value periodically, it is recommended to use the CALLBACK_WEIGHT callback. You can set the callback configuration with BrickletLoadCellV2#set_weight_callback_configuration.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 121

def get_weight
  check_validity

  send_request FUNCTION_GET_WEIGHT, [], '', 12, 'l'
end

#get_weight_callback_configuration ⇒ Object

Returns the callback configuration as set by BrickletLoadCellV2#set_weight_callback_configuration.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 159

def get_weight_callback_configuration
  check_validity

  send_request FUNCTION_GET_WEIGHT_CALLBACK_CONFIGURATION, [], '', 22, 'L ? k l l'
end

#read_uid ⇒ Object

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



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 368

def read_uid
  check_validity

  send_request FUNCTION_READ_UID, [], '', 12, 'L'
end

#register_callback(id, &block) ⇒ Object

Registers a callback with ID id to the block block.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 389

def register_callback(id, &block)
  callback = block
  @registered_callbacks[id] = callback
end

#reset ⇒ Object

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!



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 349

def reset
  check_validity

  send_request FUNCTION_RESET, [], '', 8, ''
end

#set_bootloader_mode(mode) ⇒ Object

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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 272

def set_bootloader_mode(mode)
  check_validity

  send_request FUNCTION_SET_BOOTLOADER_MODE, [mode], 'C', 9, 'C'
end

#set_configuration(rate, gain) ⇒ Object

The measurement rate and gain are configurable.

The rate can be either 10Hz or 80Hz. A faster rate will produce more noise. It is additionally possible to add a moving average (see BrickletLoadCellV2#set_moving_average) to the measurements.

The gain can be 128x, 64x or 32x. It represents a measurement range of ±20mV, ±40mV and ±80mV respectively. The Load Cell Bricklet uses an excitation voltage of 5V and most load cells use an output of 2mV/V. That means the voltage range is ±15mV for most load cells (i.e. gain of 128x is best). If you don’t know what all of this means you should keep it at 128x, it will most likely be correct.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 233

def set_configuration(rate, gain)
  check_validity

  send_request FUNCTION_SET_CONFIGURATION, [rate, gain], 'C C', 8, ''
end

#set_info_led_config(config) ⇒ Object

Configures the info LED to be either turned off, turned on, or blink in heartbeat mode.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 185

def set_info_led_config(config)
  check_validity

  send_request FUNCTION_SET_INFO_LED_CONFIG, [config], 'C', 8, ''
end

#set_moving_average(average) ⇒ Object

Sets the length of a ‘moving averaging <en.wikipedia.org/wiki/Moving_average>`__ for the weight value.

Setting the length to 1 will turn the averaging off. With less averaging, there is more noise on the data.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 170

def set_moving_average(average)
  check_validity

  send_request FUNCTION_SET_MOVING_AVERAGE, [average], 'S', 8, ''
end

#set_status_led_config(config) ⇒ Object

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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 318

def set_status_led_config(config)
  check_validity

  send_request FUNCTION_SET_STATUS_LED_CONFIG, [config], 'C', 8, ''
end

#set_weight_callback_configuration(period, value_has_to_change, option, min, max) ⇒ Object

The period is the period with which the CALLBACK_WEIGHT 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_WEIGHT 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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 152

def set_weight_callback_configuration(period, value_has_to_change, option, min, max)
  check_validity

  send_request FUNCTION_SET_WEIGHT_CALLBACK_CONFIGURATION, [period, value_has_to_change, option, min, max], 'L ? k l l', 8, ''
end

#set_write_firmware_pointer(pointer) ⇒ Object

Sets the firmware pointer for BrickletLoadCellV2#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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 291

def set_write_firmware_pointer(pointer)
  check_validity

  send_request FUNCTION_SET_WRITE_FIRMWARE_POINTER, [pointer], 'L', 8, ''
end

#tare ⇒ Object

Sets the currently measured weight as tare weight.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 215

def tare
  check_validity

  send_request FUNCTION_TARE, [], '', 8, ''
end

#write_firmware(data) ⇒ Object

Writes 64 Bytes of firmware at the position as written by BrickletLoadCellV2#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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 305

def write_firmware(data)
  check_validity

  send_request FUNCTION_WRITE_FIRMWARE, [data], 'C64', 9, 'C'
end

#write_uid(uid) ⇒ Object

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.



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# File 'lib/tinkerforge/bricklet_load_cell_v2.rb', line 360

def write_uid(uid)
  check_validity

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