LabVIEW - Dual Relay Bricklet

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

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

Examples

The example code below is Public Domain (CC0 1.0).

API

Generally, every function 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

BrickletDualRelay(uid, ipcon) → dualRelay
Input:
  • uid – Type: String
  • ipcon – Type: .NET Refnum (IPConnection)
Output:
  • dualRelay – Type: .NET Refnum (BrickletDualRelay)

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

BrickletDualRelay.SetState(relay1, relay2)
Input:
  • relay1 – Type: Boolean, Default: F
  • relay2 – Type: Boolean, Default: F

Sets the state of the relays, true means on and false means off. For example: (true, false) turns relay 1 on and relay 2 off.

If you just want to set one of the relays and don't know the current state of the other relay, you can get the state with GetState() or you can use SetSelectedState().

All running monoflop timers will be aborted if this function is called.

BrickletDualRelay.GetState() → relay1, relay2
Output:
  • relay1 – Type: Boolean, Default: F
  • relay2 – Type: Boolean, Default: F

Returns the state of the relays, true means on and false means off.

Advanced Functions

BrickletDualRelay.SetMonoflop(relay, state, time)
Input:
  • relay – Type: Byte, Range: [1 to 2]
  • state – Type: Boolean
  • time – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1]

The first parameter can be 1 or 2 (relay 1 or relay 2). The second parameter is the desired state of the relay (true means on and false means off). The third parameter indicates the time that the relay should hold the state.

If this function is called with the parameters (1, true, 1500): Relay 1 will turn on and in 1.5s it will turn off again.

A monoflop can be used as a failsafe mechanism. For example: Lets assume you have a RS485 bus and a Dual Relay Bricklet connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds. The relay will be on all the time. If now the RS485 connection is lost, the relay will turn off in at most two seconds.

BrickletDualRelay.GetMonoflop(relay) → state, time, timeRemaining
Input:
  • relay – Type: Byte, Range: [1 to 2]
Output:
  • state – Type: Boolean
  • time – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1]
  • timeRemaining – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1]

Returns (for the given relay) the current state and the time as set by SetMonoflop() as well as the remaining time until the state flips.

If the timer is not running currently, the remaining time will be returned as 0.

BrickletDualRelay.SetSelectedState(relay, state)
Input:
  • relay – Type: Byte, Range: [1 to 2]
  • state – Type: Boolean

Sets the state of the selected relay (1 or 2), true means on and false means off.

A running monoflop timer for the selected relay will be aborted if this function is called.

The other relay remains untouched.

BrickletDualRelay.GetIdentity() → uid, connectedUid, position, hardwareVersion, firmwareVersion, deviceIdentifier
Output:
  • uid – Type: String, Length: up to 8
  • connectedUid – Type: String, Length: up to 8
  • position – Type: Char, Range: ["a" to "h", "z"]
  • hardwareVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • firmwareVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • deviceIdentifier – Type: Int32, Range: [0 to 216 - 1]

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 Isolator Bricklet is always at position 'z'.

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

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 BrickletDualRelay.MonoflopDoneCallback → sender, relay, state
Callback Output:
  • sender – Type: .NET Refnum (BrickletDualRelay)
  • relay – Type: Byte, Range: [1 to 2]
  • state – Type: Boolean

This callback is triggered whenever a monoflop timer reaches 0. The parameter contain the relay (1 or 2) and the current state of the relay (the state after the monoflop).

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

BrickletDualRelay.GetAPIVersion() → apiVersion
Output:
  • apiVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]

Returns the version of the API definition 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.

BrickletDualRelay.GetResponseExpected(functionId) → responseExpected
Input:
  • functionId – Type: Byte, Range: See constants
Output:
  • responseExpected – Type: 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 sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletDualRelay.FUNCTION_SET_STATE = 1
  • BrickletDualRelay.FUNCTION_SET_MONOFLOP = 3
  • BrickletDualRelay.FUNCTION_SET_SELECTED_STATE = 6
BrickletDualRelay.SetResponseExpected(functionId, responseExpected)
Input:
  • functionId – Type: Byte, Range: See constants
  • responseExpected – Type: 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 sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletDualRelay.FUNCTION_SET_STATE = 1
  • BrickletDualRelay.FUNCTION_SET_MONOFLOP = 3
  • BrickletDualRelay.FUNCTION_SET_SELECTED_STATE = 6
BrickletDualRelay.SetResponseExpectedAll(responseExpected)
Input:
  • responseExpected – Type: Boolean

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

Constants

BrickletDualRelay.DEVICE_IDENTIFIER

This constant is used to identify a Dual Relay Bricklet.

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

BrickletDualRelay.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Dual Relay Bricklet.