Go - RGB LED Bricklet

This is the description of the Go API bindings for the RGB LED Bricklet. General information and technical specifications for the RGB LED 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/rgb_led_bricklet"
)

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

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

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

    // Set light blue color
    rl.SetRGBValue(0, 170, 234)

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

API

The RGB LED Bricklet API is defined in the package github.com/Tinkerforge/go-api-bindings/rgb_led_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 rgb_led_bricklet.New(uid string, ipcon *IPConnection) (device RGBLEDBricklet, err error)

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

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

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

func (*RGBLEDBricklet) SetRGBValue(r uint8, g uint8, b uint8) (err error)

Sets the r, g and b values for the LED. Each value can be between 0 and 255.

func (*RGBLEDBricklet) GetRGBValue() (r uint8, g uint8, b uint8, err error)

Returns the r, g and b values of the LED as set by SetRGBValue().

Advanced Functions

func (*RGBLEDBricklet) 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 (*RGBLEDBricklet) 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:

  • rgb_led_bricklet.FunctionSetRGBValue = 1
func (*RGBLEDBricklet) 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:

  • rgb_led_bricklet.FunctionSetRGBValue = 1
func (*RGBLEDBricklet) SetResponseExpectedAll(responseExpected bool) (err error)

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

func (*RGBLEDBricklet) 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.

Constants

rgb_led_bricklet.DeviceIdentifier

This constant is used to identify a RGB LED 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.

rgb_led_bricklet.DeviceDisplayName

This constant represents the human readable name of a RGB LED Bricklet.