Class: Tinkerforge::BrickletCANV2

Inherits:
Device
  • Object
show all
Defined in:
lib/tinkerforge/bricklet_can_v2.rb

Overview

Communicates with CAN bus devices

Constant Summary collapse

DEVICE_IDENTIFIER =

:nodoc:

2107
DEVICE_DISPLAY_NAME =

:nodoc:

'CAN Bricklet 2.0'
CALLBACK_FRAME_READ_LOW_LEVEL =

See CALLBACK_FRAME_READ

16
CALLBACK_FRAME_READABLE =

This callback is triggered if a data or remote frame was received by the CAN transceiver. The received frame can be read with BrickletCANV2#read_frame. If additional frames are received, but BrickletCANV2#read_frame was not called yet, the callback will not trigger again.

A configurable read filter can be used to define which frames should be received by the CAN transceiver and put into the read queue (see BrickletCANV2#set_read_filter_configuration).

To enable this callback, use BrickletCANV2#set_frame_readable_callback_configuration.

.. versionadded

2.0.3$nbsp;(Plugin)

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CALLBACK_ERROR_OCCURRED =

This callback is triggered if any error occurred while writing, reading or transmitting CAN frames.

The callback is only triggered once until BrickletCANV2#get_error_log is called. That function will return details abount the error(s) occurred.

To enable this callback, use BrickletCANV2#set_error_occurred_callback_configuration.

.. versionadded

2.0.3$nbsp;(Plugin)

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CALLBACK_FRAME_READ =

This callback is triggered if a data or remote frame was received by the CAN transceiver.

The “identifier“ return value follows the identifier format described for BrickletCANV2#write_frame.

For details on the “data“ return value see BrickletCANV2#read_frame.

A configurable read filter can be used to define which frames should be received by the CAN transceiver and put into the read queue (see BrickletCANV2#set_read_filter_configuration).

To enable this callback, use BrickletCANV2#set_frame_read_callback_configuration.

.. note

If reconstructing the value fails, the callback is triggered with nil for data.

-16
FUNCTION_WRITE_FRAME_LOW_LEVEL =

:nodoc:

1
FUNCTION_READ_FRAME_LOW_LEVEL =

:nodoc:

2
FUNCTION_SET_FRAME_READ_CALLBACK_CONFIGURATION =

:nodoc:

3
FUNCTION_GET_FRAME_READ_CALLBACK_CONFIGURATION =

:nodoc:

4
FUNCTION_SET_TRANSCEIVER_CONFIGURATION =

:nodoc:

5
FUNCTION_GET_TRANSCEIVER_CONFIGURATION =

:nodoc:

6
FUNCTION_SET_QUEUE_CONFIGURATION_LOW_LEVEL =

:nodoc:

7
FUNCTION_GET_QUEUE_CONFIGURATION_LOW_LEVEL =

:nodoc:

8
FUNCTION_SET_READ_FILTER_CONFIGURATION =

:nodoc:

9
FUNCTION_GET_READ_FILTER_CONFIGURATION =

:nodoc:

10
FUNCTION_GET_ERROR_LOG_LOW_LEVEL =

:nodoc:

11
FUNCTION_SET_COMMUNICATION_LED_CONFIG =

:nodoc:

12
FUNCTION_GET_COMMUNICATION_LED_CONFIG =

:nodoc:

13
FUNCTION_SET_ERROR_LED_CONFIG =

:nodoc:

14
FUNCTION_GET_ERROR_LED_CONFIG =

:nodoc:

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FUNCTION_SET_FRAME_READABLE_CALLBACK_CONFIGURATION =

:nodoc:

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FUNCTION_GET_FRAME_READABLE_CALLBACK_CONFIGURATION =

:nodoc:

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FUNCTION_SET_ERROR_OCCURRED_CALLBACK_CONFIGURATION =

:nodoc:

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FUNCTION_GET_ERROR_OCCURRED_CALLBACK_CONFIGURATION =

:nodoc:

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FUNCTION_GET_SPITFP_ERROR_COUNT =

:nodoc:

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FUNCTION_SET_BOOTLOADER_MODE =

:nodoc:

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FUNCTION_GET_BOOTLOADER_MODE =

:nodoc:

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FUNCTION_SET_WRITE_FIRMWARE_POINTER =

:nodoc:

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FUNCTION_WRITE_FIRMWARE =

:nodoc:

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FUNCTION_SET_STATUS_LED_CONFIG =

:nodoc:

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FUNCTION_GET_STATUS_LED_CONFIG =

:nodoc:

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FUNCTION_GET_CHIP_TEMPERATURE =

:nodoc:

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FUNCTION_RESET =

:nodoc:

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FUNCTION_WRITE_UID =

:nodoc:

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FUNCTION_READ_UID =

:nodoc:

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FUNCTION_GET_IDENTITY =

:nodoc:

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FRAME_TYPE_STANDARD_DATA =

:nodoc:

0
FRAME_TYPE_STANDARD_REMOTE =

:nodoc:

1
FRAME_TYPE_EXTENDED_DATA =

:nodoc:

2
FRAME_TYPE_EXTENDED_REMOTE =

:nodoc:

3
TRANSCEIVER_MODE_NORMAL =

:nodoc:

0
TRANSCEIVER_MODE_LOOPBACK =

:nodoc:

1
TRANSCEIVER_MODE_READ_ONLY =

:nodoc:

2
FILTER_MODE_ACCEPT_ALL =

:nodoc:

0
FILTER_MODE_MATCH_STANDARD_ONLY =

:nodoc:

1
FILTER_MODE_MATCH_EXTENDED_ONLY =

:nodoc:

2
FILTER_MODE_MATCH_STANDARD_AND_EXTENDED =

:nodoc:

3
TRANSCEIVER_STATE_ACTIVE =

:nodoc:

0
TRANSCEIVER_STATE_PASSIVE =

:nodoc:

1
TRANSCEIVER_STATE_DISABLED =

:nodoc:

2
COMMUNICATION_LED_CONFIG_OFF =

:nodoc:

0
COMMUNICATION_LED_CONFIG_ON =

:nodoc:

1
COMMUNICATION_LED_CONFIG_SHOW_HEARTBEAT =

:nodoc:

2
COMMUNICATION_LED_CONFIG_SHOW_COMMUNICATION =

:nodoc:

3
ERROR_LED_CONFIG_OFF =

:nodoc:

0
ERROR_LED_CONFIG_ON =

:nodoc:

1
ERROR_LED_CONFIG_SHOW_HEARTBEAT =

:nodoc:

2
ERROR_LED_CONFIG_SHOW_TRANSCEIVER_STATE =

:nodoc:

3
ERROR_LED_CONFIG_SHOW_ERROR =

:nodoc:

4
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) ⇒ BrickletCANV2

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_can_v2.rb', line 138

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

  @api_version = [2, 0, 1]

  @response_expected[FUNCTION_WRITE_FRAME_LOW_LEVEL] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_READ_FRAME_LOW_LEVEL] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_FRAME_READ_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_FRAME_READ_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_TRANSCEIVER_CONFIGURATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_TRANSCEIVER_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_QUEUE_CONFIGURATION_LOW_LEVEL] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_QUEUE_CONFIGURATION_LOW_LEVEL] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_READ_FILTER_CONFIGURATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_READ_FILTER_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_ERROR_LOG_LOW_LEVEL] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_COMMUNICATION_LED_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_COMMUNICATION_LED_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ERROR_LED_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_ERROR_LED_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_FRAME_READABLE_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_FRAME_READABLE_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ERROR_OCCURRED_CALLBACK_CONFIGURATION] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ERROR_OCCURRED_CALLBACK_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_FRAME_READ_LOW_LEVEL] = [29, 'C L C C15']
  @callback_formats[CALLBACK_FRAME_READABLE] = [8, '']
  @callback_formats[CALLBACK_ERROR_OCCURRED] = [8, '']

  @high_level_callbacks[CALLBACK_FRAME_READ] = [[nil, nil, 'stream_length', 'stream_chunk_data'], {'fixed_length' => nil, 'single_chunk' => true}, nil]
  @ipcon.add_device self
end

Instance Method Details

#get_bootloader_mode ⇒ Object

Returns the current bootloader mode, see BrickletCANV2#set_bootloader_mode.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 573

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_can_v2.rb', line 631

def get_chip_temperature
  check_validity

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

#get_communication_led_config ⇒ Object

Returns the configuration as set by BrickletCANV2#set_communication_led_config



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 468

def get_communication_led_config
  check_validity

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

#get_error_led_config ⇒ Object

Returns the configuration as set by BrickletCANV2#set_error_led_config.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 494

def get_error_led_config
  check_validity

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

#get_error_log ⇒ Object

Returns information about different kinds of errors.

The write and read error levels indicate the current level of stuffing, form, acknowledgement, bit and checksum errors during CAN bus write and read operations. For each of this error kinds there is also an individual counter.

When the write error level extends 255 then the CAN transceiver gets disabled and no frames can be transmitted or received anymore. The CAN transceiver will automatically be activated again after the CAN bus is idle for a while.

The write buffer timeout, read buffer and backlog overflow counts represents the number of these errors:

  • A write buffer timeout occurs if a frame could not be transmitted before the configured write buffer timeout expired (see BrickletCANV2#set_queue_configuration).

  • A read buffer overflow occurs if a read buffer of the CAN transceiver still contains the last received frame when the next frame arrives. In this case the last received frame is lost. This happens if the CAN transceiver receives more frames than the Bricklet can handle. Using the read filter (see BrickletCANV2#set_read_filter_configuration) can help to reduce the amount of received frames. This count is not exact, but a lower bound, because the Bricklet might not able detect all overflows if they occur in rapid succession.

  • A read backlog overflow occurs if the read backlog of the Bricklet is already full when the next frame should be read from a read buffer of the CAN transceiver. In this case the frame in the read buffer is lost. This happens if the CAN transceiver receives more frames to be added to the read backlog than are removed from the read backlog using the BrickletCANV2#read_frame function. Using the CALLBACK_FRAME_READ callback ensures that the read backlog can not overflow.

The read buffer overflow counter counts the overflows of all configured read buffers. Which read buffer exactly suffered from an overflow can be figured out from the read buffer overflow occurrence list (“read_buffer_overflow_error_occurred“). Reading the error log clears the occurence list.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 859

def get_error_log
  ret = get_error_log_low_level

  [ret[0], ret[1], ret[2], ret[3], ret[4], ret[5], ret[6], ret[7], ret[8], ret[9], ret[10], ret[12][0, ret[11]], ret[13]]
end

#get_error_log_low_level ⇒ Object

Returns information about different kinds of errors.

The write and read error levels indicate the current level of stuffing, form, acknowledgement, bit and checksum errors during CAN bus write and read operations. For each of this error kinds there is also an individual counter.

When the write error level extends 255 then the CAN transceiver gets disabled and no frames can be transmitted or received anymore. The CAN transceiver will automatically be activated again after the CAN bus is idle for a while.

The write buffer timeout, read buffer and backlog overflow counts represents the number of these errors:

  • A write buffer timeout occurs if a frame could not be transmitted before the configured write buffer timeout expired (see BrickletCANV2#set_queue_configuration).

  • A read buffer overflow occurs if a read buffer of the CAN transceiver still contains the last received frame when the next frame arrives. In this case the last received frame is lost. This happens if the CAN transceiver receives more frames than the Bricklet can handle. Using the read filter (see BrickletCANV2#set_read_filter_configuration) can help to reduce the amount of received frames. This count is not exact, but a lower bound, because the Bricklet might not able detect all overflows if they occur in rapid succession.

  • A read backlog overflow occurs if the read backlog of the Bricklet is already full when the next frame should be read from a read buffer of the CAN transceiver. In this case the frame in the read buffer is lost. This happens if the CAN transceiver receives more frames to be added to the read backlog than are removed from the read backlog using the BrickletCANV2#read_frame function. Using the CALLBACK_FRAME_READ callback ensures that the read backlog can not overflow.

The read buffer overflow counter counts the overflows of all configured read buffers. Which read buffer exactly suffered from an overflow can be figured out from the read buffer overflow occurrence list (“read_buffer_overflow_error_occurred“). Reading the error log clears the occurence list.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 449

def get_error_log_low_level
  check_validity

  send_request FUNCTION_GET_ERROR_LOG_LOW_LEVEL, [], '', 52, 'C C C L L L L L L L L C ?32 L'
end

#get_error_occurred_callback_configuration ⇒ Object

Returns true if the CALLBACK_ERROR_OCCURRED callback is enabled, false otherwise.

.. versionadded

2.0.3$nbsp;(Plugin)



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 534

def get_error_occurred_callback_configuration
  check_validity

  send_request FUNCTION_GET_ERROR_OCCURRED_CALLBACK_CONFIGURATION, [], '', 9, '?'
end

#get_frame_read_callback_configuration ⇒ Object

Returns true if the CALLBACK_FRAME_READ callback is enabled, false otherwise.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 255

def get_frame_read_callback_configuration
  check_validity

  send_request FUNCTION_GET_FRAME_READ_CALLBACK_CONFIGURATION, [], '', 9, '?'
end

#get_frame_readable_callback_configuration ⇒ Object

Returns true if the CALLBACK_FRAME_READABLE callback is enabled, false otherwise.

.. versionadded

2.0.3$nbsp;(Plugin)



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 514

def get_frame_readable_callback_configuration
  check_validity

  send_request FUNCTION_GET_FRAME_READABLE_CALLBACK_CONFIGURATION, [], '', 9, '?'
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_can_v2.rb', line 678

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

#get_queue_configuration ⇒ Object

Returns the queue configuration as set by BrickletCANV2#set_queue_configuration.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 818

def get_queue_configuration
  ret = get_queue_configuration_low_level

  [ret[0], ret[1], ret[2], ret[4][0, ret[3]], ret[5]]
end

#get_queue_configuration_low_level ⇒ Object

Returns the queue configuration as set by BrickletCANV2#set_queue_configuration.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 339

def get_queue_configuration_low_level
  check_validity

  send_request FUNCTION_GET_QUEUE_CONFIGURATION_LOW_LEVEL, [], '', 50, 'C l S C c32 S'
end

#get_read_filter_configuration(buffer_index) ⇒ Object

Returns the read filter configuration as set by BrickletCANV2#set_read_filter_configuration.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 408

def get_read_filter_configuration(buffer_index)
  check_validity

  send_request FUNCTION_GET_READ_FILTER_CONFIGURATION, [buffer_index], 'C', 17, 'C L L'
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_can_v2.rb', line 551

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 BrickletCANV2#set_status_led_config



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 619

def get_status_led_config
  check_validity

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

#get_transceiver_configuration ⇒ Object

Returns the configuration as set by BrickletCANV2#set_transceiver_configuration.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 279

def get_transceiver_configuration
  check_validity

  send_request FUNCTION_GET_TRANSCEIVER_CONFIGURATION, [], '', 15, 'L S C'
end

#read_frame ⇒ Object

Tries to read the next data or remote frame from the read queue and returns it. If a frame was successfully read, then the “success“ return value is set to true and the other return values contain the frame. If the read queue is empty and no frame could be read, then the “success“ return value is set to false and the other return values contain invalid data.

The “identifier“ return value follows the identifier format described for BrickletCANV2#write_frame.

The “data“ return value can be up to 15 bytes long. For data frames up to the first 8 bytes are the actual received data. All bytes after the 8th byte are always zero and only there to indicate the length of a data or remote frame with excess length. For remote frames the length of the “data“ return value represents the requested length. The actual “data“ bytes are always zero.

A configurable read filter can be used to define which frames should be received by the CAN transceiver and put into the read queue (see BrickletCANV2#set_read_filter_configuration).

Instead of polling with this function, you can also use callbacks. See the BrickletCANV2#set_frame_read_callback_configuration function and the CALLBACK_FRAME_READ callback.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 748

def read_frame
  ret = read_frame_low_level

  [ret[0], ret[1], ret[2], ret[4][0, ret[3]]]
end

#read_frame_low_level ⇒ Object

Tries to read the next data or remote frame from the read queue and returns it. If a frame was successfully read, then the “success“ return value is set to true and the other return values contain the frame. If the read queue is empty and no frame could be read, then the “success“ return value is set to false and the other return values contain invalid data.

The “identifier“ return value follows the identifier format described for BrickletCANV2#write_frame.

The “data“ return value can be up to 15 bytes long. For data frames up to the first 8 bytes are the actual received data. All bytes after the 8th byte are always zero and only there to indicate the length of a data or remote frame with excess length. For remote frames the length of the “data“ return value represents the requested length. The actual “data“ bytes are always zero.

A configurable read filter can be used to define which frames should be received by the CAN transceiver and put into the read queue (see BrickletCANV2#set_read_filter_configuration).

Instead of polling with this function, you can also use callbacks. See the BrickletCANV2#set_frame_read_callback_configuration function and the CALLBACK_FRAME_READ callback.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 239

def read_frame_low_level
  check_validity

  send_request FUNCTION_READ_FRAME_LOW_LEVEL, [], '', 30, '? C L C C15'
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_can_v2.rb', line 662

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_can_v2.rb', line 866

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_can_v2.rb', line 643

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_can_v2.rb', line 566

def set_bootloader_mode(mode)
  check_validity

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

#set_communication_led_config(config) ⇒ Object

Sets the communication LED configuration. By default the LED shows CAN-Bus traffic, it flickers once for every 40 transmitted or received frames.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is off.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 461

def set_communication_led_config(config)
  check_validity

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

#set_error_led_config(config) ⇒ Object

Sets the error LED configuration.

By default (show-transceiver-state) the error LED turns on if the CAN transceiver is passive or disabled state (see BrickletCANV2#get_error_log). If the CAN transceiver is in active state the LED turns off.

If the LED is configured as show-error then the error LED turns on if any error occurs. If you call this function with the show-error option again, the LED will turn off until the next error occurs.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is off.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 487

def set_error_led_config(config)
  check_validity

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

#set_error_occurred_callback_configuration(enabled) ⇒ Object

Enables and disables the CALLBACK_ERROR_OCCURRED callback.

By default the callback is disabled.

.. versionadded

2.0.3$nbsp;(Plugin)



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 525

def set_error_occurred_callback_configuration(enabled)
  check_validity

  send_request FUNCTION_SET_ERROR_OCCURRED_CALLBACK_CONFIGURATION, [enabled], '?', 8, ''
end

#set_frame_read_callback_configuration(enabled) ⇒ Object

Enables and disables the CALLBACK_FRAME_READ callback.

By default the callback is disabled. Enabling this callback will disable the CALLBACK_FRAME_READABLE callback.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 248

def set_frame_read_callback_configuration(enabled)
  check_validity

  send_request FUNCTION_SET_FRAME_READ_CALLBACK_CONFIGURATION, [enabled], '?', 8, ''
end

#set_frame_readable_callback_configuration(enabled) ⇒ Object

Enables and disables the CALLBACK_FRAME_READABLE callback.

By default the callback is disabled. Enabling this callback will disable the CALLBACK_FRAME_READ callback.

.. versionadded

2.0.3$nbsp;(Plugin)



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 505

def set_frame_readable_callback_configuration(enabled)
  check_validity

  send_request FUNCTION_SET_FRAME_READABLE_CALLBACK_CONFIGURATION, [enabled], '?', 8, ''
end

#set_queue_configuration(write_buffer_size, write_buffer_timeout, write_backlog_size, read_buffer_sizes, read_backlog_size) ⇒ Object

Sets the write and read queue configuration.

The CAN transceiver has 32 buffers in total in hardware for transmitting and receiving frames. Additionally, the Bricklet has a backlog for 768 frames in total in software. The buffers and the backlog can be freely assigned to the write and read queues.

BrickletCANV2#write_frame writes a frame into the write backlog. The Bricklet moves the frame from the backlog into a free write buffer. The CAN transceiver then transmits the frame from the write buffer to the CAN bus. If there are no write buffers (“write_buffer_size“ is zero) or there is no write backlog (“write_backlog_size“ is zero) then no frames can be transmitted and BrickletCANV2#write_frame returns always false.

The CAN transceiver receives a frame from the CAN bus and stores it into a free read buffer. The Bricklet moves the frame from the read buffer into the read backlog. BrickletCANV2#read_frame reads the frame from the read backlog and returns it. If there are no read buffers (“read_buffer_sizes“ is empty) or there is no read backlog (“read_backlog_size“ is zero) then no frames can be received and BrickletCANV2#read_frame returns always false.

There can be multiple read buffers, because the CAN transceiver cannot receive data and remote frames into the same read buffer. A positive read buffer size represents a data frame read buffer and a negative read buffer size represents a remote frame read buffer. A read buffer size of zero is not allowed. By default the first read buffer is configured for data frames and the second read buffer is configured for remote frame. There can be up to 32 different read buffers, assuming that no write buffer is used. Each read buffer has its own filter configuration (see BrickletCANV2#set_read_filter_configuration).

A valid queue configuration fulfills these conditions

write_buffer_size + abs(read_buffer_size_0) + abs(read_buffer_size_1) + … + abs(read_buffer_size_31) <= 32 write_backlog_size + read_backlog_size <= 768

The write buffer timeout has three different modes that define how a failed frame transmission should be handled:

  • Single-Shot (< 0): Only one transmission attempt will be made. If the transmission fails then the frame is discarded.

  • Infinite (= 0): Infinite transmission attempts will be made. The frame will never be discarded.

  • Milliseconds (> 0): A limited number of transmission attempts will be made. If the frame could not be transmitted successfully after the configured number of milliseconds then the frame is discarded.

The current content of the queues is lost when this function is called.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 801

def set_queue_configuration(write_buffer_size, write_buffer_timeout, write_backlog_size, read_buffer_sizes, read_backlog_size)
  read_buffer_sizes = read_buffer_sizes.clone # clone so we can potentially extend it
  read_buffer_sizes_length = read_buffer_sizes.length
  read_buffer_sizes_data = read_buffer_sizes

  if read_buffer_sizes_length > 32
    raise ArgumentError, 'Read Buffer Sizes can be at most 32 items long'
  end

  if read_buffer_sizes_length < 32
    read_buffer_sizes_data += [0] * (32 - read_buffer_sizes_length)
  end

  set_queue_configuration_low_level write_buffer_size, write_buffer_timeout, write_backlog_size, read_buffer_sizes_length, read_buffer_sizes_data, read_backlog_size
end

#set_queue_configuration_low_level(write_buffer_size, write_buffer_timeout, write_backlog_size, read_buffer_sizes_length, read_buffer_sizes_data, read_backlog_size) ⇒ Object

Sets the write and read queue configuration.

The CAN transceiver has 32 buffers in total in hardware for transmitting and receiving frames. Additionally, the Bricklet has a backlog for 768 frames in total in software. The buffers and the backlog can be freely assigned to the write and read queues.

BrickletCANV2#write_frame writes a frame into the write backlog. The Bricklet moves the frame from the backlog into a free write buffer. The CAN transceiver then transmits the frame from the write buffer to the CAN bus. If there are no write buffers (“write_buffer_size“ is zero) or there is no write backlog (“write_backlog_size“ is zero) then no frames can be transmitted and BrickletCANV2#write_frame returns always false.

The CAN transceiver receives a frame from the CAN bus and stores it into a free read buffer. The Bricklet moves the frame from the read buffer into the read backlog. BrickletCANV2#read_frame reads the frame from the read backlog and returns it. If there are no read buffers (“read_buffer_sizes“ is empty) or there is no read backlog (“read_backlog_size“ is zero) then no frames can be received and BrickletCANV2#read_frame returns always false.

There can be multiple read buffers, because the CAN transceiver cannot receive data and remote frames into the same read buffer. A positive read buffer size represents a data frame read buffer and a negative read buffer size represents a remote frame read buffer. A read buffer size of zero is not allowed. By default the first read buffer is configured for data frames and the second read buffer is configured for remote frame. There can be up to 32 different read buffers, assuming that no write buffer is used. Each read buffer has its own filter configuration (see BrickletCANV2#set_read_filter_configuration).

A valid queue configuration fulfills these conditions

write_buffer_size + abs(read_buffer_size_0) + abs(read_buffer_size_1) + … + abs(read_buffer_size_31) <= 32 write_backlog_size + read_backlog_size <= 768

The write buffer timeout has three different modes that define how a failed frame transmission should be handled:

  • Single-Shot (< 0): Only one transmission attempt will be made. If the transmission fails then the frame is discarded.

  • Infinite (= 0): Infinite transmission attempts will be made. The frame will never be discarded.

  • Milliseconds (> 0): A limited number of transmission attempts will be made. If the frame could not be transmitted successfully after the configured number of milliseconds then the frame is discarded.

The current content of the queues is lost when this function is called.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 332

def set_queue_configuration_low_level(write_buffer_size, write_buffer_timeout, write_backlog_size, read_buffer_sizes_length, read_buffer_sizes_data, read_backlog_size)
  check_validity

  send_request FUNCTION_SET_QUEUE_CONFIGURATION_LOW_LEVEL, [write_buffer_size, write_buffer_timeout, write_backlog_size, read_buffer_sizes_length, read_buffer_sizes_data, read_backlog_size], 'C l S C c32 S', 8, ''
end

#set_read_filter_configuration(buffer_index, filter_mode, filter_mask, filter_identifier) ⇒ Object

Set the read filter configuration for the given read buffer index. This can be used to define which frames should be received by the CAN transceiver and put into the read buffer.

The read filter has four different modes that define if and how the filter mask and the filter identifier are applied:

  • Accept-All: All frames are received.

  • Match-Standard-Only: Only standard frames with a matching identifier are received.

  • Match-Extended-Only: Only extended frames with a matching identifier are received.

  • Match-Standard-And-Extended: Standard and extended frames with a matching identifier are received.

The filter mask and filter identifier are used as bit masks. Their usage depends on the mode:

  • Accept-All: Mask and identifier are ignored.

  • Match-Standard-Only: Bit 0 to 10 (11 bits) of filter mask and filter identifier are used to match the 11-bit identifier of standard frames.

  • Match-Extended-Only: Bit 0 to 28 (29 bits) of filter mask and filter identifier are used to match the 29-bit identifier of extended frames.

  • Match-Standard-And-Extended: Bit 18 to 28 (11 bits) of filter mask and filter identifier are used to match the 11-bit identifier of standard frames, bit 0 to 17 (18 bits) are ignored in this case. Bit 0 to 28 (29 bits) of filter mask and filter identifier are used to match the 29-bit identifier of extended frames.

The filter mask and filter identifier are applied in this way: The filter mask is used to select the frame identifier bits that should be compared to the corresponding filter identifier bits. All unselected bits are automatically accepted. All selected bits have to match the filter identifier to be accepted. If all bits for the selected mode are accepted then the frame is accepted and is added to the read buffer.

"Filter Mask Bit", "Filter Identifier Bit", "Frame Identifier Bit", "Result"

0, X, X, Accept
1, 0, 0, Accept
1, 0, 1, Reject
1, 1, 0, Reject
1, 1, 1, Accept

For example, to receive standard frames with identifier 0x123 only, the mode can be set to Match-Standard-Only with 0x7FF as mask and 0x123 as identifier. The mask of 0x7FF selects all 11 identifier bits for matching so that the identifier has to be exactly 0x123 to be accepted.

To accept identifier 0x123 and identifier 0x456 at the same time, just set filter 2 to 0x456 and keep mask and filter 1 unchanged.

There can be up to 32 different read filters configured at the same time, because there can be up to 32 read buffer (see BrickletCANV2#set_queue_configuration).

The default mode is accept-all for all read buffers.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 401

def set_read_filter_configuration(buffer_index, filter_mode, filter_mask, filter_identifier)
  check_validity

  send_request FUNCTION_SET_READ_FILTER_CONFIGURATION, [buffer_index, filter_mode, filter_mask, filter_identifier], 'C C L L', 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_can_v2.rb', line 612

def set_status_led_config(config)
  check_validity

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

#set_transceiver_configuration(baud_rate, sample_point, transceiver_mode) ⇒ Object

Sets the transceiver configuration for the CAN bus communication.

The CAN transceiver has three different modes:

  • Normal: Reads from and writes to the CAN bus and performs active bus error detection and acknowledgement.

  • Loopback: All reads and writes are performed internally. The transceiver is disconnected from the actual CAN bus.

  • Read-Only: Only reads from the CAN bus, but does neither active bus error detection nor acknowledgement. Only the receiving part of the transceiver is connected to the CAN bus.



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 272

def set_transceiver_configuration(baud_rate, sample_point, transceiver_mode)
  check_validity

  send_request FUNCTION_SET_TRANSCEIVER_CONFIGURATION, [baud_rate, sample_point, transceiver_mode], 'L S C', 8, ''
end

#set_write_firmware_pointer(pointer) ⇒ Object

Sets the firmware pointer for BrickletCANV2#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_can_v2.rb', line 585

def set_write_firmware_pointer(pointer)
  check_validity

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

#write_firmware(data) ⇒ Object

Writes 64 Bytes of firmware at the position as written by BrickletCANV2#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_can_v2.rb', line 599

def write_firmware(data)
  check_validity

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

#write_frame(frame_type, identifier, data) ⇒ Object

Writes a data or remote frame to the write queue to be transmitted over the CAN transceiver.

The Bricklet supports the standard 11-bit (CAN 2.0A) and the additional extended 29-bit (CAN 2.0B) identifiers. For standard frames the Bricklet uses bit 0 to 10 from the “identifier“ parameter as standard 11-bit identifier. For extended frames the Bricklet uses bit 0 to 28 from the “identifier“ parameter as extended 29-bit identifier.

The “data“ parameter can be up to 15 bytes long. For data frames up to 8 bytes will be used as the actual data. The length (DLC) field in the data or remote frame will be set to the actual length of the “data“ parameter. This allows to transmit data and remote frames with excess length. For remote frames only the length of the “data“ parameter is used. The actual “data“ bytes are ignored.

Returns true if the frame was successfully added to the write queue. Returns false if the frame could not be added because write queue is already full or because the write buffer or the write backlog are configured with a size of zero (see BrickletCANV2#set_queue_configuration).

The write queue can overflow if frames are written to it at a higher rate than the Bricklet can transmitted them over the CAN transceiver. This may happen if the CAN transceiver is configured as read-only or is using a low baud rate (see BrickletCANV2#set_transceiver_configuration). It can also happen if the CAN bus is congested and the frame cannot be transmitted because it constantly loses arbitration or because the CAN transceiver is currently disabled due to a high write error level (see BrickletCANV2#get_error_log).



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 710

def write_frame(frame_type, identifier, data)
  data = data.clone # clone so we can potentially extend it
  data_length = data.length
  data_data = data

  if data_length > 15
    raise ArgumentError, 'Data can be at most 15 items long'
  end

  if data_length < 15
    data_data += [0] * (15 - data_length)
  end

  write_frame_low_level frame_type, identifier, data_length, data_data
end

#write_frame_low_level(frame_type, identifier, data_length, data_data) ⇒ Object

Writes a data or remote frame to the write queue to be transmitted over the CAN transceiver.

The Bricklet supports the standard 11-bit (CAN 2.0A) and the additional extended 29-bit (CAN 2.0B) identifiers. For standard frames the Bricklet uses bit 0 to 10 from the “identifier“ parameter as standard 11-bit identifier. For extended frames the Bricklet uses bit 0 to 28 from the “identifier“ parameter as extended 29-bit identifier.

The “data“ parameter can be up to 15 bytes long. For data frames up to 8 bytes will be used as the actual data. The length (DLC) field in the data or remote frame will be set to the actual length of the “data“ parameter. This allows to transmit data and remote frames with excess length. For remote frames only the length of the “data“ parameter is used. The actual “data“ bytes are ignored.

Returns true if the frame was successfully added to the write queue. Returns false if the frame could not be added because write queue is already full or because the write buffer or the write backlog are configured with a size of zero (see BrickletCANV2#set_queue_configuration).

The write queue can overflow if frames are written to it at a higher rate than the Bricklet can transmitted them over the CAN transceiver. This may happen if the CAN transceiver is configured as read-only or is using a low baud rate (see BrickletCANV2#set_transceiver_configuration). It can also happen if the CAN bus is congested and the frame cannot be transmitted because it constantly loses arbitration or because the CAN transceiver is currently disabled due to a high write error level (see BrickletCANV2#get_error_log).



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# File 'lib/tinkerforge/bricklet_can_v2.rb', line 211

def write_frame_low_level(frame_type, identifier, data_length, data_data)
  check_validity

  send_request FUNCTION_WRITE_FRAME_LOW_LEVEL, [frame_type, identifier, data_length, data_data], 'C L C C15', 9, '?'
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_can_v2.rb', line 654

def write_uid(uid)
  check_validity

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