Delphi/Lazarus - Industrial Digital In 4 Bricklet

This is the description of the Delphi/Lazarus API bindings for the Industrial Digital In 4 Bricklet. General information and technical specifications for the Industrial Digital In 4 Bricklet are summarized in its hardware description.

An installation guide for the Delphi/Lazarus API bindings is part of their general description.

Examples

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

Simple

Download (ExampleSimple.pas)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
program ExampleSimple;

{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}

uses
  SysUtils, IPConnection, BrickletIndustrialDigitalIn4;

type
  TExample = class
  private
    ipcon: TIPConnection;
    idi4: TBrickletIndustrialDigitalIn4;
  public
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; { Change XYZ to the UID of your Industrial Digital In 4 Bricklet }

var
  e: TExample;

procedure TExample.Execute;
var valueMask: word;
begin
  { Create IP connection }
  ipcon := TIPConnection.Create;

  { Create device object }
  idi4 := TBrickletIndustrialDigitalIn4.Create(UID, ipcon);

  { Connect to brickd }
  ipcon.Connect(HOST, PORT);
  { Don't use device before ipcon is connected }

  { Get current value as bitmask }
  valueMask := idi4.GetValue;
  WriteLn(Format('Value Mask: %d', [valueMask]));

  WriteLn('Press key to exit');
  ReadLn;
  ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;

begin
  e := TExample.Create;
  e.Execute;
  e.Destroy;
end.

Interrupt

Download (ExampleInterrupt.pas)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
program ExampleInterrupt;

{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}

uses
  SysUtils, IPConnection, BrickletIndustrialDigitalIn4;

type
  TExample = class
  private
    ipcon: TIPConnection;
    idi4: TBrickletIndustrialDigitalIn4;
  public
    procedure InterruptCB(sender: TBrickletIndustrialDigitalIn4;
                          const interruptMask: word; const valueMask: word);
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; { Change XYZ to the UID of your Industrial Digital In 4 Bricklet }

var
  e: TExample;

{ Callback procedure for interrupt callback }
procedure TExample.InterruptCB(sender: TBrickletIndustrialDigitalIn4;
                               const interruptMask: word; const valueMask: word);
begin
  WriteLn(Format('Interrupt Mask: %d', [interruptMask]));
  WriteLn(Format('Value Mask: %d', [valueMask]));
  WriteLn('');
end;

procedure TExample.Execute;
begin
  { Create IP connection }
  ipcon := TIPConnection.Create;

  { Create device object }
  idi4 := TBrickletIndustrialDigitalIn4.Create(UID, ipcon);

  { Connect to brickd }
  ipcon.Connect(HOST, PORT);
  { Don't use device before ipcon is connected }

  { Register interrupt callback to procedure InterruptCB }
  idi4.OnInterrupt := {$ifdef FPC}@{$endif}InterruptCB;

  { Enable interrupt on pin 0 }
  idi4.SetInterrupt(1 shl 0);

  WriteLn('Press key to exit');
  ReadLn;
  ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;

begin
  e := TExample.Create;
  e.Execute;
  e.Destroy;
end.

API

Since Delphi does not support multiple return values directly, we use the out keyword to return multiple values from a function.

All functions and procedures listed below are thread-safe.

Basic Functions

constructor TBrickletIndustrialDigitalIn4.Create(const uid: string; ipcon: TIPConnection)
Parameters:
  • uid – Type: string
  • ipcon – Type: TIPConnection
Returns:
  • industrialDigitalIn4 – Type: TBrickletIndustrialDigitalIn4

Creates an object with the unique device ID uid:

industrialDigitalIn4 := TBrickletIndustrialDigitalIn4.Create('YOUR_DEVICE_UID', ipcon);

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

function TBrickletIndustrialDigitalIn4.GetValue: word
Returns:
  • valueMask – Type: word, Range: [0 to 216 - 1]

Returns the input value with a bitmask. The bitmask is 16bit long, true refers to high and false refers to low.

For example: The value 3 or 0b0011 means that pins 0-1 are high and the other pins are low.

If no groups are used (see SetGroup), the pins correspond to the markings on the IndustrialDigital In 4 Bricklet.

If groups are used, the pins correspond to the element in the group. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.

function TBrickletIndustrialDigitalIn4.GetEdgeCount(const pin: byte; const resetCounter: boolean): longword
Parameters:
  • pin – Type: byte, Range: [0 to 3]
  • resetCounter – Type: boolean
Returns:
  • count – Type: longword, Range: [0 to 232 - 1]

Returns the current value of the edge counter for the selected pin. You can configure the edges that are counted with SetEdgeCountConfig.

If you set the reset counter to true, the count is set back to 0 directly after it is read.

The edge counters use the grouping as set by SetGroup.

New in version 2.0.1 (Plugin).

Advanced Functions

procedure TBrickletIndustrialDigitalIn4.SetGroup(const group: array [0..3] of char)
Parameters:
  • group – Type: array [0..3] of char, Range: ['a' to 'd', 'n']

Sets a group of Digital In 4 Bricklets that should work together. You can find Bricklets that can be grouped together with GetAvailableForGroup.

The group consists of 4 elements. Element 1 in the group will get pins 0-3, element 2 pins 4-7, element 3 pins 8-11 and element 4 pins 12-15.

Each element can either be one of the ports ('a' to 'd') or 'n' if it should not be used.

For example: If you have two Digital In 4 Bricklets connected to port A and port B respectively, you could call with ['a', 'b', 'n', 'n'].

Now the pins on the Digital In 4 on port A are assigned to 0-3 and the pins on the Digital In 4 on port B are assigned to 4-7. It is now possible to call GetValue and read out two Bricklets at the same time.

Changing the group configuration resets all edge counter configurations and values.

function TBrickletIndustrialDigitalIn4.GetGroup: array [0..3] of char
Returns:
  • group – Type: array [0..3] of char, Range: ['a' to 'd', 'n']

Returns the group as set by SetGroup

function TBrickletIndustrialDigitalIn4.GetAvailableForGroup: byte
Returns:
  • available – Type: byte, Range: [0 to 15]

Returns a bitmask of ports that are available for grouping. For example the value 5 or 0b0101 means: Port A and port C are connected to Bricklets that can be grouped together.

procedure TBrickletIndustrialDigitalIn4.SetEdgeCountConfig(const selectionMask: word; const edgeType: byte; const debounce: byte)
Parameters:
  • selectionMask – Type: word, Range: [0 to 216 - 1]
  • edgeType – Type: byte, Range: See constants, Default: 0
  • debounce – Type: byte, Unit: 1 ms, Range: [0 to 255], Default: 100

Configures the edge counter for the selected pins. A bitmask of 9 or 0b1001 will enable the edge counter for pins 0 and 3.

The edge type parameter configures if rising edges, falling edges or both are counted if the pin is configured for input. Possible edge types are:

  • 0 = rising
  • 1 = falling
  • 2 = both

Configuring an edge counter resets its value to 0.

If you don't know what any of this means, just leave it at default. The default configuration is very likely OK for you.

The edge counters use the grouping as set by SetGroup.

The following constants are available for this function:

For edgeType:

  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_EDGE_TYPE_RISING = 0
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_EDGE_TYPE_FALLING = 1
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_EDGE_TYPE_BOTH = 2

New in version 2.0.1 (Plugin).

procedure TBrickletIndustrialDigitalIn4.GetEdgeCountConfig(const pin: byte; out edgeType: byte; out debounce: byte)
Parameters:
  • pin – Type: byte, Range: [0 to 255]
Output Parameters:
  • edgeType – Type: byte, Range: See constants, Default: 0
  • debounce – Type: byte, Unit: 1 ms, Range: [0 to 255], Default: 100

Returns the edge type and debounce time for the selected pin as set by SetEdgeCountConfig.

The following constants are available for this function:

For edgeType:

  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_EDGE_TYPE_RISING = 0
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_EDGE_TYPE_FALLING = 1
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_EDGE_TYPE_BOTH = 2

New in version 2.0.1 (Plugin).

procedure TBrickletIndustrialDigitalIn4.GetIdentity(out uid: string; out connectedUid: string; out position: char; out hardwareVersion: array [0..2] of byte; out firmwareVersion: array [0..2] of byte; out deviceIdentifier: word)
Output Parameters:
  • uid – Type: string, Length: up to 8
  • connectedUid – Type: string, Length: up to 8
  • position – Type: char, Range: ['a' to 'h', 'i', 'z']
  • hardwareVersion – Type: array [0..2] of byte
    • 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: array [0..2] of byte
    • 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: word, 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). The Raspberry Pi HAT (Zero) Brick is always at position 'i' and the Bricklet connected to an Isolator Bricklet is always as 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

procedure TBrickletIndustrialDigitalIn4.SetDebouncePeriod(const debounce: longword)
Parameters:
  • debounce – Type: longword, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Sets the debounce period of the OnInterrupt callback.

For example: If you set this value to 100, you will get the interrupt maximal every 100ms. This is necessary if something that bounces is connected to the Digital In 4 Bricklet, such as a button.

function TBrickletIndustrialDigitalIn4.GetDebouncePeriod: longword
Returns:
  • debounce – Type: longword, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Returns the debounce period as set by SetDebouncePeriod.

procedure TBrickletIndustrialDigitalIn4.SetInterrupt(const interruptMask: word)
Parameters:
  • interruptMask – Type: word, Range: [0 to 216 - 1]

Sets the pins on which an interrupt is activated with a bitmask. Interrupts are triggered on changes of the voltage level of the pin, i.e. changes from high to low and low to high.

For example: An interrupt bitmask of 9 or 0b1001 will enable the interrupt for pins 0 and 3.

The interrupts use the grouping as set by SetGroup.

The interrupt is delivered with the OnInterrupt callback.

function TBrickletIndustrialDigitalIn4.GetInterrupt: word
Returns:
  • interruptMask – Type: word, Range: [0 to 216 - 1]

Returns the interrupt bitmask as set by SetInterrupt.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a procedure to an callback property of the device object:

procedure TExample.MyCallback(sender: TBrickletIndustrialDigitalIn4; const value: longint);
begin
  WriteLn(Format('Value: %d', [value]));
end;

industrialDigitalIn4.OnExample := {$ifdef FPC}@{$endif}example.MyCallback;

The available callback properties and their parameter types 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.

property TBrickletIndustrialDigitalIn4.OnInterrupt
procedure(sender: TBrickletIndustrialDigitalIn4; const interruptMask: word; const valueMask: word) of object;
Callback Parameters:
  • sender – Type: TBrickletIndustrialDigitalIn4
  • interruptMask – Type: word, Range: [0 to 216 - 1]
  • valueMask – Type: word, Range: [0 to 216 - 1]

This callback is triggered whenever a change of the voltage level is detected on pins where the interrupt was activated with SetInterrupt.

The values are a bitmask that specifies which interrupts occurred and the current value bitmask.

For example:

  • (1, 1) or (0b0001, 0b0001) means that an interrupt on pin 0 occurred and currently pin 0 is high and pins 1-3 are low.
  • (9, 14) or (0b1001, 0b1110) means that interrupts on pins 0 and 3 occurred and currently pin 0 is low and pins 1-3 are high.

The interrupts use the grouping as set by SetGroup.

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.

function TBrickletIndustrialDigitalIn4.GetAPIVersion: array [0..2] of byte
Output Parameters:
  • apiVersion – Type: array [0..2] of byte
    • 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.

function TBrickletIndustrialDigitalIn4.GetResponseExpected(const functionId: byte): boolean
Parameters:
  • functionId – Type: byte, 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 functionId:

  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_GROUP = 2
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_DEBOUNCE_PERIOD = 5
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_INTERRUPT = 7
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_EDGE_COUNT_CONFIG = 11
procedure TBrickletIndustrialDigitalIn4.SetResponseExpected(const functionId: byte; const responseExpected: boolean)
Parameters:
  • 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:

  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_GROUP = 2
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_DEBOUNCE_PERIOD = 5
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_INTERRUPT = 7
  • BRICKLET_INDUSTRIAL_DIGITAL_IN_4_FUNCTION_SET_EDGE_COUNT_CONFIG = 11
procedure TBrickletIndustrialDigitalIn4.SetResponseExpectedAll(const responseExpected: boolean)
Parameters:
  • responseExpected – Type: boolean

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

Constants

const BRICKLET_INDUSTRIAL_DIGITAL_IN_4_DEVICE_IDENTIFIER

This constant is used to identify a Industrial Digital In 4 Bricklet.

The GetIdentity function and the TIPConnection.OnEnumerate callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

const BRICKLET_INDUSTRIAL_DIGITAL_IN_4_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Industrial Digital In 4 Bricklet.