LabVIEW - Hall Effect Bricklet

This is the description of the LabVIEW API bindings for the Hall Effect Bricklet. General information and technical specifications for the Hall Effect Bricklet are summarized in its hardware description.

An installation guide for the LabVIEW API bindings is part of their general description.

API

Generally, every method of the LabVIEW bindings that outputs a value can report a Tinkerforge.TimeoutException. This error gets reported if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody plugs the device out). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.

Basic Functions

BrickletHallEffect(uid, ipcon) → hallEffect
Input:
  • uid -- String
  • ipcon -- .NET Refnum (IPConnection)
Output:
  • hallEffect -- .NET Refnum (BrickletHallEffect)

Creates an object with the unique device ID uid. This object can then be used after the IP Connection is connected (see examples above).

BrickletHallEffect.GetValue() → value
Output:
  • value -- Boolean

Returns true if a magnetic field of 35 Gauss (3.5mT) or greater is detected.

BrickletHallEffect.GetEdgeCount(resetCounter) → count
Input:
  • resetCounter -- Boolean
Output:
  • count -- Int64

Returns the current value of the edge counter. You can configure edge type (rising, falling, both) that is counted with SetEdgeCountConfig().

If you set the reset counter to true, the count is set back to 0 directly after it is read.

Advanced Functions

BrickletHallEffect.SetEdgeCountConfig(edgeType, debounce)
Input:
  • edgeType -- Byte
  • debounce -- Byte

The edge type parameter configures if rising edges, falling edges or both are counted. Possible edge types are:

  • 0 = rising (default)
  • 1 = falling
  • 2 = both

A magnetic field of 35 Gauss (3.5mT) or greater causes a falling edge and a magnetic field of 25 Gauss (2.5mT) or smaller causes a rising edge.

If a magnet comes near the Bricklet the signal goes low (falling edge), if a magnet is removed from the vicinity the signal goes high (rising edge).

The debounce time is given in ms.

Configuring an edge counter resets its value to 0.

If you don't know what any of this means, just leave it at default. The default configuration is very likely OK for you.

Default values: 0 (edge type) and 100ms (debounce time)

The following constants are available for this function:

  • BrickletHallEffect.EDGE_TYPE_RISING = 0
  • BrickletHallEffect.EDGE_TYPE_FALLING = 1
  • BrickletHallEffect.EDGE_TYPE_BOTH = 2
BrickletHallEffect.GetEdgeCountConfig() → edgeType, debounce
Output:
  • edgeType -- Byte
  • debounce -- Byte

Returns the edge type and debounce time as set by SetEdgeCountConfig().

The following constants are available for this function:

  • BrickletHallEffect.EDGE_TYPE_RISING = 0
  • BrickletHallEffect.EDGE_TYPE_FALLING = 1
  • BrickletHallEffect.EDGE_TYPE_BOTH = 2
BrickletHallEffect.GetAPIVersion() → apiVersion
Output:
  • apiVersion -- Byte[3]

Returns the version of the API definition (major, minor, revision) 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.

BrickletHallEffect.GetResponseExpected(functionId) → responseExpected
Input:
  • functionId -- Byte
Output:
  • responseExpected -- Boolean

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 SetResponseExpected(). 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 send and errors are silently ignored, because they cannot be detected.

See SetResponseExpected() for the list of function ID constants available for this function.

BrickletHallEffect.SetResponseExpected(functionId, responseExpected)
Input:
  • functionId -- Byte
  • responseExpected -- Boolean

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 send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BrickletHallEffect.FUNCTION_SET_EDGE_COUNT_CONFIG = 3
  • BrickletHallEffect.FUNCTION_SET_EDGE_INTERRUPT = 5
  • BrickletHallEffect.FUNCTION_SET_EDGE_COUNT_CALLBACK_PERIOD = 7
BrickletHallEffect.SetResponseExpectedAll(responseExpected)
Input:
  • responseExpected -- Boolean

Changes the response expected flag for all setter and callback configuration functions of this device at once.

BrickletHallEffect.GetIdentity() → uid, connectedUid, position, hardwareVersion, firmwareVersion, deviceIdentifier
Output:
  • uid -- String
  • connectedUid -- String
  • position -- Char
  • hardwareVersion -- Byte[3]
  • firmwareVersion -- Byte[3]
  • deviceIdentifier -- Int32

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' or 'd'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

BrickletHallEffect.SetEdgeInterrupt(edges)
Input:
  • edges -- Int64

Sets the number of edges until an interrupt is invoked.

If edges is set to n, an interrupt is invoked for every n-th detected edge.

If edges is set to 0, the interrupt is disabled.

Default value is 0.

BrickletHallEffect.GetEdgeInterrupt() → edges
Output:
  • edges -- Int64

Returns the edges as set by SetEdgeInterrupt().

BrickletHallEffect.SetEdgeCountCallbackPeriod(period)
Input:
  • period -- Int64

Sets the period in ms with which the EdgeCountCallback callback is triggered periodically. A value of 0 turns the callback off.

The EdgeCountCallback callback is only triggered if the edge count has changed since the last triggering.

The default value is 0.

BrickletHallEffect.GetEdgeCountCallbackPeriod() → period
Output:
  • period -- Int64

Returns the period as set by SetEdgeCountCallbackPeriod().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a function to a callback property of the device object. The available callback property and their 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.

event BrickletHallEffect.EdgeCountCallback(sender, count, value)
Input:
  • sender -- .NET Refnum (BrickletHallEffect)
  • count -- Int64
  • value -- Boolean

This callback is triggered periodically with the period that is set by SetEdgeCountCallbackPeriod(). The parameters are the current count and the current value (see GetValue() and GetEdgeCount()).

The EdgeCountCallback callback is only triggered if the count or value changed since the last triggering.

Constants

BrickletHallEffect.DEVICE_IDENTIFIER

This constant is used to identify a Hall Effect Bricklet.

The GetIdentity() function and the EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

BrickletHallEffect.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Hall Effect Bricklet.