Go - Tilt Bricklet

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

An installation guide for the Go API bindings is part of their general description. Additional documentation can be found on godoc.org.

Examples

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

Simple

Download (example_simple.go)

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package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
    "github.com/Tinkerforge/go-api-bindings/tilt_bricklet"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your Tilt Bricklet.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    t, _ := tilt_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // Don't use device before ipcon is connected.

    // Get current tilt state.
    state, _ := t.GetTiltState()

    if state == tilt_bricklet.TiltStateClosed {
        fmt.Println("Tilt State: Closed")
    } else if state == tilt_bricklet.TiltStateOpen {
        fmt.Println("Tilt State: Open")
    } else if state == tilt_bricklet.TiltStateClosedVibrating {
        fmt.Println("Tilt State: Closed Vibrating")
    }

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

Callback

Download (example_callback.go)

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package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
    "github.com/Tinkerforge/go-api-bindings/tilt_bricklet"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your Tilt Bricklet.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    t, _ := tilt_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // Don't use device before ipcon is connected.

    // Enable tilt state callback
    t.EnableTiltStateCallback()

    t.RegisterTiltStateCallback(func(state tilt_bricklet.TiltState) {

        if state == tilt_bricklet.TiltStateClosed {
            fmt.Println("Tilt State: Closed")
        } else if state == tilt_bricklet.TiltStateOpen {
            fmt.Println("Tilt State: Open")
        } else if state == tilt_bricklet.TiltStateClosedVibrating {
            fmt.Println("Tilt State: Closed Vibrating")
        }
    })

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

API

The Tilt Bricklet's API is defined in the package github.com/Tinkerforge/go-api-bindings/tilt_bricklet

Nearly every function of the Go bindings can return an BrickletError, implementing the error interface. The error can have one of the following values:

  • BrickletErrorSuccess = 0
  • BrickletErrorInvalidParameter = 1
  • BrickletErrorFunctionNotSupported = 2
  • BrickletErrorUnknownError = 3

which correspond to the values returned from Bricks and Bricklets.

All functions listed below are thread-safe.

Basic Functions

func NewTiltBricklet(uid string, ipcon *IPConnection)(device TiltBricklet, err error)

Creates a new TiltBricklet object with the unique device ID uid and adds it to the IPConnection ipcon:

This device object can be used after the IP connection has been connected (see examples above).

func (*TiltBricklet)GetTiltState()(state TiltState, err error)

Returns the current tilt state. The state can either be

  • 0 = Closed: The ball in the tilt switch closes the circuit.
  • 1 = Open: The ball in the tilt switch does not close the circuit.
  • 2 = Closed Vibrating: The tilt switch is in motion (rapid change between open and close).
Tilt states

The following constants are available for this function:

  • TiltStateClosed = 0
  • TiltStateOpen = 1
  • TiltStateClosedVibrating = 2

Advanced Functions

func (*TiltBricklet)GetAPIVersion()(apiVersion [3]uint8, err error)

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.

func (*TiltBricklet)GetResponseExpected(functionId uint8)(responseExpected bool, err error)

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

func (*TiltBricklet)SetResponseExpected(functionId uint8, responseExpected bool)(err error)

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:

  • FunctionEnableTiltStateCallback = 2
  • FunctionDisableTiltStateCallback = 3
func (*TiltBricklet)SetResponseExpectedAll(responseExpected bool)(err error)

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

func (*TiltBricklet)GetIdentity()(uid string, connectedUid string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, err error)

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

func (*TiltBricklet)EnableTiltStateCallback()(err error)

Enables the (*TiltBricklet) RegisterTiltStateCallback callback.

func (*TiltBricklet)DisableTiltStateCallback()(err error)

Disables the (*TiltBricklet) RegisterTiltStateCallback callback.

func (*TiltBricklet)IsTiltStateCallbackEnabled()(enabled bool, err error)

Returns true if the (*TiltBricklet) RegisterTiltStateCallback callback is enabled.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding Register*Callback function, which returns a unique callback ID. This ID can be used to deregister the callback later.

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.

func (*TiltBricklet)RegisterTiltStateCallback(func(state TiltState))(callbackID uint64)

A callback can be registered for this event with the RegisterTiltStateCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterTiltStateCallback(callbackID uint64) function.

This callback provides the current tilt state. It is called every time the state changes.

See (*TiltBricklet) GetTiltState for a description of the states.

The following constants are available for this function:

  • TiltStateClosed = 0
  • TiltStateOpen = 1
  • TiltStateClosedVibrating = 2

Constants

tilt_bricklet.DeviceIdentifier

This constant is used to identify a Tilt Bricklet.

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

tilt_bricklet.DeviceDisplayName

This constant represents the human readable name of a Tilt Bricklet.