Go - Motion Detector Bricklet

This is the description of the Go API bindings for the Motion Detector Bricklet. General information and technical specifications for the Motion Detector 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).

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/motion_detector_bricklet"
)

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

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

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

    md.RegisterMotionDetectedCallback(func() {
        fmt.Println("Motion Detected")
    })

    md.RegisterDetectionCycleEndedCallback(func() {
        fmt.Println("Detection Cycle Ended (next detection possible in ~3 seconds)")
    })

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

API

The Motion Detector Bricklet API is defined in the package github.com/Tinkerforge/go-api-bindings/motion_detector_bricklet

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

  • DeviceErrorSuccess = 0
  • DeviceErrorInvalidParameter = 1
  • DeviceErrorFunctionNotSupported = 2
  • DeviceErrorUnknownError = 3

which correspond to the values returned from Bricks and Bricklets.

All functions listed below are thread-safe.

Basic Functions

func motion_detector_bricklet.New(uid string, ipcon *IPConnection) (device MotionDetectorBricklet, err error)

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

device, err := motion_detector_bricklet.New("YOUR_DEVICE_UID", &ipcon)

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

func (*MotionDetectorBricklet) GetMotionDetected() (motion Motion, err error)

Returns 1 if a motion was detected. How long this returns 1 after a motion was detected can be adjusted with one of the small potentiometers on the Motion Detector Bricklet, see here.

There is also a blue LED on the Bricklet that is on as long as the Bricklet is in the "motion detected" state.

The following constants are available for this function:

  • motion_detector_bricklet.MotionNotDetected = 0
  • motion_detector_bricklet.MotionDetected = 1

Advanced Functions

func (*MotionDetectorBricklet) SetStatusLEDConfig(config StatusLEDConfig) (err error)

Sets the status led configuration.

By default the status LED turns on if a motion is detected and off is no motion is detected.

You can also turn the LED permanently on/off.

The following constants are available for this function:

  • motion_detector_bricklet.StatusLEDConfigOff = 0
  • motion_detector_bricklet.StatusLEDConfigOn = 1
  • motion_detector_bricklet.StatusLEDConfigShowStatus = 2

New in version 2.0.1 (Plugin).

func (*MotionDetectorBricklet) GetStatusLEDConfig() (config StatusLEDConfig, err error)

Returns the configuration as set by SetStatusLEDConfig().

The following constants are available for this function:

  • motion_detector_bricklet.StatusLEDConfigOff = 0
  • motion_detector_bricklet.StatusLEDConfigOn = 1
  • motion_detector_bricklet.StatusLEDConfigShowStatus = 2

New in version 2.0.1 (Plugin).

func (*MotionDetectorBricklet) 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 (*MotionDetectorBricklet) GetResponseExpected(functionId Function) (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 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.

The following constants are available for this function:

  • motion_detector_bricklet.FunctionSetStatusLEDConfig = 4
func (*MotionDetectorBricklet) SetResponseExpected(functionId Function, 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 constants are available for this function:

  • motion_detector_bricklet.FunctionSetStatusLEDConfig = 4
func (*MotionDetectorBricklet) SetResponseExpectedAll(responseExpected bool) (err error)

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

func (*MotionDetectorBricklet) 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.

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 (*MotionDetectorBricklet) RegisterMotionDetectedCallback(func()) (registrationId uint64)

A callback can be registered for this event with the RegisterMotionDetectedCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterMotionDetectedCallback(registrationId uint64) function.

This callback is called after a motion was detected.

func (*MotionDetectorBricklet) RegisterDetectionCycleEndedCallback(func()) (registrationId uint64)

A callback can be registered for this event with the RegisterDetectionCycleEndedCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterDetectionCycleEndedCallback(registrationId uint64) function.

This callback is called when the detection cycle ended. When this callback is called, a new motion can be detected again after approximately 2 seconds.

Constants

motion_detector_bricklet.DeviceIdentifier

This constant is used to identify a Motion Detector Bricklet.

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

motion_detector_bricklet.DeviceDisplayName

This constant represents the human readable name of a Motion Detector Bricklet.