Software / API Bindings / JavaScript / API Reference and Examples / Bricklets / Segment Display 4x7 Bricklet

JavaScript - Segment Display 4x7 Bricklet¶

This is the description of the JavaScript API bindings for the Segment Display 4x7 Bricklet. General information and technical specifications for the Segment Display 4x7 Bricklet are summarized in its hardware description.

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

Examples¶

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

Simple (Node.js)¶

Download (ExampleSimple.js)

var Tinkerforge = require('tinkerforge');

var HOST = 'localhost';
var PORT = 4223;
var UID = 'XYZ'; // Change XYZ to the UID of your Segment Display 4x7 Bricklet
var DIGITS = [0x3f,0x06,0x5b,0x4f,
              0x66,0x6d,0x7d,0x07,
              0x7f,0x6f,0x77,0x7c,
              0x39,0x5e,0x79,0x71]; // 0~9,A,b,C,d,E,F

var ipcon = new Tinkerforge.IPConnection(); // Create IP connection
var sd = new Tinkerforge.BrickletSegmentDisplay4x7(UID, ipcon); // Create device object

ipcon.connect(HOST, PORT,
    function (error) {
        console.log('Error: ' + error);
    }
); // Connect to brickd
// Don't use device before ipcon is connected

ipcon.on(Tinkerforge.IPConnection.CALLBACK_CONNECTED,
    function (connectReason) {
        // Write "4223" to the display with full brightness without colon
        var segments = [DIGITS[4], DIGITS[2], DIGITS[2], DIGITS[3]];
        sd.setSegments(segments, 7, false);
    }
);

console.log('Press key to exit');
process.stdin.on('data',
    function (data) {
        ipcon.disconnect();
        process.exit(0);
    }
);

Simple (HTML)¶

Download (ExampleSimple.html), Test (ExampleSimple.html)

<!DOCTYPE html>
<html>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <head>
        <title>Tinkerforge | JavaScript Example</title>
    </head>
    <body>
        <div style="text-align:center;">
            <h1>Segment Display 4x7 Bricklet Simple Example</h1>
            <p>
                <input value="localhost" id="host" type="text" size="20">:
                <input value="4280" id="port" type="text" size="5">,
                <input value="uid" id="uid" type="text" size="5">
                <input value="Start Example" id="start" type="button" onclick="startExample();">
            </p>
            <p>
                <textarea readonly id="text" cols="80" rows="24" style="resize:none;"
                          >Press "Start Example" to begin ...</textarea>
            </p>
        </div>
        <script src="./Tinkerforge.js" type='text/javascript'></script>
        <script type='text/javascript'>
            var ipcon;
            var textArea = document.getElementById("text");
            function startExample() {
                textArea.value = "";
                var HOST = document.getElementById("host").value;
                var PORT = parseInt(document.getElementById("port").value);
                var UID = document.getElementById("uid").value;
                if(ipcon !== undefined) {
                    ipcon.disconnect();
                }
                var DIGITS = [0x3f,0x06,0x5b,0x4f,
                              0x66,0x6d,0x7d,0x07,
                              0x7f,0x6f,0x77,0x7c,
                              0x39,0x5e,0x79,0x71]; // 0~9,A,b,C,d,E,F
                ipcon = new Tinkerforge.IPConnection(); // Create IP connection
                var sd = new Tinkerforge.BrickletSegmentDisplay4x7(UID, ipcon); // Create device object
                ipcon.connect(HOST, PORT,
                    function(error) {
                        textArea.value += 'Error: ' + error + '\n';
                    }
                ); // Connect to brickd
                // Don't use device before ipcon is connected

                ipcon.on(Tinkerforge.IPConnection.CALLBACK_CONNECTED,
                    function (connectReason) {
                        // Write "4223" to the display with full brightness without colon
                        var segments = [DIGITS[4], DIGITS[2], DIGITS[2], DIGITS[3]];
                        sd.setSegments(segments, 7, false);
                    }
                );
            }
        </script>
    </body>
</html>

API¶

Generally, every function of the JavaScript bindings can take two optional parameters, returnCallback and errorCallback. These are two user defined callback functions. The returnCallback function is called with the results as arguments, if the function returns its results asynchronously. The errorCallback is called with an error code in case of an error. The error code can be one of the following values:

IPConnection.ERROR_ALREADY_CONNECTED = 11
IPConnection.ERROR_NOT_CONNECTED = 12
IPConnection.ERROR_CONNECT_FAILED = 13
IPConnection.ERROR_INVALID_FUNCTION_ID = 21
IPConnection.ERROR_TIMEOUT = 31
IPConnection.ERROR_INVALID_PARAMETER = 41
IPConnection.ERROR_FUNCTION_NOT_SUPPORTED = 42
IPConnection.ERROR_UNKNOWN_ERROR = 43
IPConnection.ERROR_STREAM_OUT_OF_SYNC = 51
IPConnection.ERROR_NON_ASCII_CHAR_IN_SECRET = 71
IPConnection.ERROR_WRONG_DEVICE_TYPE = 81
IPConnection.ERROR_DEVICE_REPLACED = 82
IPConnection.ERROR_WRONG_RESPONSE_LENGTH = 83
IPConnection.ERROR_INT64_NOT_SUPPORTED = 91

The namespace for the JavaScript bindings is Tinkerforge.*.

Basic Functions¶

new BrickletSegmentDisplay4x7(uid, ipcon)¶

Parameters:	uid – Type: string ipcon – Type: IPConnection
Returns:	segmentDisplay4x7 – Type: BrickletSegmentDisplay4x7

Creates an object with the unique device ID uid:

var segmentDisplay4x7 = new BrickletSegmentDisplay4x7("YOUR_DEVICE_UID", ipcon);

This object can then be used after the IP Connection is connected.

BrickletSegmentDisplay4x7.setSegments(segments, brightness, colon[, returnCallback][, errorCallback])¶

Parameters:	segments – Type: [int, ...], Length: 4, Range: [0 to 127] brightness – Type: int, Range: [0 to 7] colon – Type: boolean
Callback Parameters:	undefined
Returns:	undefined

The 7-segment display can be set with bitmaps. Every bit controls one segment:

For example to set a "5" you would want to activate segments 0, 2, 3, 5 and 6. This is represented by the number 0b01101101 = 0x6d = 109.

The brightness can be set between 0 (dark) and 7 (bright). The colon parameter turns the colon of the display on or off.

BrickletSegmentDisplay4x7.getSegments([returnCallback][, errorCallback])¶

Callback Parameters:	segments – Type: [int, ...], Length: 4, Range: [0 to 127] brightness – Type: int, Range: [0 to 7] colon – Type: boolean
Returns:	undefined

Returns the segment, brightness and color data as set by setSegments().

Advanced Functions¶

BrickletSegmentDisplay4x7.startCounter(valueFrom, valueTo, increment, length[, returnCallback][, errorCallback])¶

Parameters:	valueFrom – Type: int, Range: [-999 to 9999] valueTo – Type: int, Range: [-999 to 9999] increment – Type: int, Range: [-999 to 9999] length – Type: int, Unit: 1 ms, Range: [0 to 2³² - 1]
Callback Parameters:	undefined
Returns:	undefined

Starts a counter with the from value that counts to the to value with the each step incremented by increment. length is the pause between each increment.

Example: If you set from to 0, to to 100, increment to 1 and length to 1000, a counter that goes from 0 to 100 with one second pause between each increment will be started.

Using a negative increment allows to count backwards.

You can stop the counter at every time by calling setSegments().

BrickletSegmentDisplay4x7.getCounterValue([returnCallback][, errorCallback])¶

Callback Parameters:	value – Type: int, Range: [-999 to 9999]
Returns:	undefined

Returns the counter value that is currently shown on the display.

If there is no counter running a 0 will be returned.

BrickletSegmentDisplay4x7.getIdentity([returnCallback][, errorCallback])¶

Callback Parameters:

Callback Parameters:	uid – Type: string, Length: up to 8 connectedUid – Type: string, Length: up to 8 position – Type: char, Range: ['a' to 'h', 'z'] hardwareVersion – Type: [int, ...], Length: 3 0: major – Type: int, Range: [0 to 255] 1: minor – Type: int, Range: [0 to 255] 2: revision – Type: int, Range: [0 to 255] firmwareVersion – Type: [int, ...], Length: 3 0: major – Type: int, Range: [0 to 255] 1: minor – Type: int, Range: [0 to 255] 2: revision – Type: int, Range: [0 to 255] deviceIdentifier – Type: int, Range: [0 to 2¹⁶ - 1]
Returns:	undefined

uid – Type: string, Length: up to 8
connectedUid – Type: string, Length: up to 8
position – Type: char, Range: ['a' to 'h', 'z']
hardwareVersion – Type: [int, ...], Length: 3

0: major – Type: int, Range: [0 to 255]
1: minor – Type: int, Range: [0 to 255]
2: revision – Type: int, Range: [0 to 255]

firmwareVersion – Type: [int, ...], Length: 3

0: major – Type: int, Range: [0 to 255]
1: minor – Type: int, Range: [0 to 255]
2: revision – Type: int, Range: [0 to 255]

deviceIdentifier – Type: int, Range: [0 to 2¹⁶ - 1]

Returns:

undefined

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.

Callback Configuration Functions¶

BrickletSegmentDisplay4x7.on(callback_id, function[, errorCallback])¶

Parameters:	callback_id – Type: int function – Type: function
Returns:	undefined

Registers the given function with the given callback_id.

The available callback IDs with corresponding function signatures are listed below.

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the on() function of the device object. The first parameter is the callback ID and the second parameter the callback function:

segmentDisplay4x7.on(BrickletSegmentDisplay4x7.CALLBACK_EXAMPLE,
    function (param) {
        console.log(param);
    }
);

The available constants with inherent number and 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.

BrickletSegmentDisplay4x7.CALLBACK_COUNTER_FINISHED¶

Callback Parameters:	undefined

This callback is triggered when the counter (see startCounter()) is finished.

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.

BrickletSegmentDisplay4x7.getAPIVersion()¶

Returns:	apiVersion – Type: [int, ...], Length: 3 0: major – Type: int, Range: [0 to 255] 1: minor – Type: int, Range: [0 to 255] 2: revision – Type: int, 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.

BrickletSegmentDisplay4x7.getResponseExpected(functionId[, errorCallback])¶

Parameters:	functionId – Type: int, Range: See constants
Returns:	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 function_id:

BrickletSegmentDisplay4x7.FUNCTION_SET_SEGMENTS = 1
BrickletSegmentDisplay4x7.FUNCTION_START_COUNTER = 3

BrickletSegmentDisplay4x7.setResponseExpected(functionId, responseExpected[, errorCallback])¶

Parameters:	functionId – Type: int, Range: See constants responseExpected – Type: boolean
Returns:	undefined

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.

The following constants are available for this function:

For function_id:

BrickletSegmentDisplay4x7.FUNCTION_SET_SEGMENTS = 1
BrickletSegmentDisplay4x7.FUNCTION_START_COUNTER = 3

BrickletSegmentDisplay4x7.setResponseExpectedAll(responseExpected)¶

Parameters:	responseExpected – Type: boolean
Returns:	undefined

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

Constants¶

BrickletSegmentDisplay4x7.DEVICE_IDENTIFIER¶

This constant is used to identify a Segment Display 4x7 Bricklet.

The getIdentity() function and the IPConnection.CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

BrickletSegmentDisplay4x7.DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a Segment Display 4x7 Bricklet.