Class: Tinkerforge::BrickletMultiTouch

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

Overview

Capacitive touch sensor for 12 electrodes

Constant Summary collapse

DEVICE_IDENTIFIER =

:nodoc:

234
DEVICE_DISPLAY_NAME =

:nodoc:

'Multi Touch Bricklet'
CALLBACK_TOUCH_STATE =

Returns the current touch state, see BrickletMultiTouch#get_touch_state for information about the state.

This callback is triggered every time the touch state changes.

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FUNCTION_GET_TOUCH_STATE =

:nodoc:

1
FUNCTION_RECALIBRATE =

:nodoc:

2
FUNCTION_SET_ELECTRODE_CONFIG =

:nodoc:

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FUNCTION_GET_ELECTRODE_CONFIG =

:nodoc:

4
FUNCTION_SET_ELECTRODE_SENSITIVITY =

:nodoc:

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FUNCTION_GET_ELECTRODE_SENSITIVITY =

:nodoc:

7
FUNCTION_GET_IDENTITY =

:nodoc:

255

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) ⇒ BrickletMultiTouch

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_multi_touch.rb', line 37

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

  @api_version = [2, 0, 0]

  @response_expected[FUNCTION_GET_TOUCH_STATE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_RECALIBRATE] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_SET_ELECTRODE_CONFIG] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_ELECTRODE_CONFIG] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ELECTRODE_SENSITIVITY] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_ELECTRODE_SENSITIVITY] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IDENTITY] = RESPONSE_EXPECTED_ALWAYS_TRUE

  @callback_formats[CALLBACK_TOUCH_STATE] = [10, 'S']

  @ipcon.add_device self
end

Instance Method Details

#get_electrode_config ⇒ Object

Returns the electrode configuration, as set by BrickletMultiTouch#set_electrode_config.



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# File 'lib/tinkerforge/bricklet_multi_touch.rb', line 108

def get_electrode_config
  check_validity

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

#get_electrode_sensitivity ⇒ Object

Returns the current sensitivity, as set by BrickletMultiTouch#set_electrode_sensitivity.



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# File 'lib/tinkerforge/bricklet_multi_touch.rb', line 130

def get_electrode_sensitivity
  check_validity

  send_request FUNCTION_GET_ELECTRODE_SENSITIVITY, [], '', 9, '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_multi_touch.rb', line 146

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

#get_touch_state ⇒ Object

Returns the current touch state. The state is given as a bitfield.

Bits 0 to 11 represent the 12 electrodes and bit 12 represents the proximity.

If an electrode is touched, the corresponding bit is true. If a hand or similar is in proximity to the electrodes, bit 12 is true.

Example: The state 4103 = 0x1007 = 0b1000000000111 means that electrodes 0, 1 and 2 are touched and that something is in the proximity of the electrodes.

The proximity is activated with a distance of 1-2cm. An electrode is already counted as touched if a finger is nearly touching the electrode. This means that you can put a piece of paper or foil or similar on top of a electrode to build a touch panel with a professional look.



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# File 'lib/tinkerforge/bricklet_multi_touch.rb', line 73

def get_touch_state
  check_validity

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

#recalibrate ⇒ Object

Recalibrates the electrodes. Call this function whenever you changed or moved you electrodes.



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

def recalibrate
  check_validity

  send_request FUNCTION_RECALIBRATE, [], '', 8, ''
end

#register_callback(id, &block) ⇒ Object

Registers a callback with ID id to the block block.



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# File 'lib/tinkerforge/bricklet_multi_touch.rb', line 151

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

#set_electrode_config(enabled_electrodes) ⇒ Object

Enables/disables electrodes with a bitfield (see BrickletMultiTouch#get_touch_state).

True enables the electrode, false disables the electrode. A disabled electrode will always return false as its state. If you don’t need all electrodes you can disable the electrodes that are not needed.

It is recommended that you disable the proximity bit (bit 12) if the proximity feature is not needed. This will reduce the amount of traffic that is produced by the CALLBACK_TOUCH_STATE callback.

Disabling electrodes will also reduce power consumption.

Default: 8191 = 0x1FFF = 0b1111111111111 (all electrodes and proximity feature enabled)



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# File 'lib/tinkerforge/bricklet_multi_touch.rb', line 101

def set_electrode_config(enabled_electrodes)
  check_validity

  send_request FUNCTION_SET_ELECTRODE_CONFIG, [enabled_electrodes], 'S', 8, ''
end

#set_electrode_sensitivity(sensitivity) ⇒ Object

Sets the sensitivity of the electrodes. An electrode with a high sensitivity will register a touch earlier then an electrode with a low sensitivity.

If you build a big electrode you might need to decrease the sensitivity, since the area that can be charged will get bigger. If you want to be able to activate an electrode from further away you need to increase the sensitivity.

After a new sensitivity is set, you likely want to call BrickletMultiTouch#recalibrate to calibrate the electrodes with the newly defined sensitivity.



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# File 'lib/tinkerforge/bricklet_multi_touch.rb', line 123

def set_electrode_sensitivity(sensitivity)
  check_validity

  send_request FUNCTION_SET_ELECTRODE_SENSITIVITY, [sensitivity], 'C', 8, ''
end