Delphi/Lazarus - Industrial Digital Out 4 Bricklet

This is the description of the Delphi/Lazarus API bindings for the Industrial Digital Out 4 Bricklet. General information and technical specifications for the Industrial Digital Out 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)

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program ExampleSimple;

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

uses
  SysUtils, IPConnection, BrickletIndustrialDigitalOut4;

type
  TExample = class
  private
    ipcon: TIPConnection;
    ido4: TBrickletIndustrialDigitalOut4;
  public
    procedure Execute;
  end;

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

var
  e: TExample;

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

  { Create device object }
  ido4 := TBrickletIndustrialDigitalOut4.Create(UID, ipcon);

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

  { Set pins alternating high/low 10 times with 100ms delay }
  for i := 0 to 9 do begin
    Sleep(100);
    ido4.SetValue(1 shl 0);
    Sleep(100);
    ido4.SetValue(1 shl 1);
    Sleep(100);
    ido4.SetValue(1 shl 2);
    Sleep(100);
    ido4.SetValue(1 shl 3);
  end;

  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 TBrickletIndustrialDigitalOut4.Create(const uid: string; ipcon: TIPConnection)

Creates an object with the unique device ID uid:

industrialDigitalOut4 := TBrickletIndustrialDigitalOut4.Create('YOUR_DEVICE_UID', ipcon);

This object can then be used after the IP Connection is connected (see examples above).

procedure TBrickletIndustrialDigitalOut4.SetValue(const valueMask: word)

Sets the output value with a bitmask (16bit). A 1 in the bitmask means high and a 0 in the bitmask means low.

For example: The value 3 or 0b0011 will turn pins 0-1 high and the other pins low.

If no groups are used (see SetGroup), the pins correspond to the markings on the Digital Out 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 TBrickletIndustrialDigitalOut4.GetValue: word

Returns the bitmask as set by SetValue.

procedure TBrickletIndustrialDigitalOut4.SetSelectedValues(const selectionMask: word; const valueMask: word)

Sets the output value with a bitmask, according to the selection mask. The bitmask is 16 bit long, true refers to high and false refers to low.

For example: The values (3, 1) or (0b0011, 0b0001) will turn pin 0 high, pin 1 low the other pins remain untouched.

If no groups are used (see SetGroup), the pins correspond to the markings on the Digital Out 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.

Advanced Functions

procedure TBrickletIndustrialDigitalOut4.SetMonoflop(const selectionMask: word; const valueMask: word; const time: longword)

Configures a monoflop of the pins specified by the first parameter bitmask.

The second parameter is a bitmask with the desired value of the specified pins. A 1 in the bitmask means high and a 0 in the bitmask means low.

The third parameter indicates the time (in ms) that the pins should hold the value.

If this function is called with the parameters (9, 1, 1500) or (0b1001, 0b0001, 1500): Pin 0 will get high and pin 3 will get low. In 1.5s pin 0 will get low and pin 3 will get high again.

A monoflop can be used as a fail-safe mechanism. For example: Lets assume you have a RS485 bus and a Digital Out 4 Bricklet connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds and pin 0 high. Pin 0 will be high all the time. If now the RS485 connection is lost, then pin 0 will turn low in at most two seconds.

procedure TBrickletIndustrialDigitalOut4.GetMonoflop(const pin: byte; out value: word; out time: longword; out timeRemaining: longword)

Returns (for the given pin) the current value and the time as set by SetMonoflop as well as the remaining time until the value flips.

If the timer is not running currently, the remaining time will be returned as 0.

procedure TBrickletIndustrialDigitalOut4.SetGroup(const group: array [0..3] of char)

Sets a group of Digital Out 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 Out 4 Bricklets connected to port A and port B respectively, you could call with ['a', 'b', 'n', 'n'].

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

function TBrickletIndustrialDigitalOut4.GetGroup: array [0..3] of char

Returns the group as set by SetGroup

function TBrickletIndustrialDigitalOut4.GetAvailableForGroup: byte

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.

function TBrickletIndustrialDigitalOut4.GetAPIVersion: array [0..2] of byte

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.

function TBrickletIndustrialDigitalOut4.GetResponseExpected(const functionId: byte): 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 send and errors are silently ignored, because they cannot be detected.

See SetResponseExpected for the list of function ID constants available for this function.

procedure TBrickletIndustrialDigitalOut4.SetResponseExpected(const functionId: byte; const responseExpected: 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 send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BRICKLET_INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_VALUE = 1
  • BRICKLET_INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_MONOFLOP = 3
  • BRICKLET_INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_GROUP = 5
  • BRICKLET_INDUSTRIAL_DIGITAL_OUT_4_FUNCTION_SET_SELECTED_VALUES = 9
procedure TBrickletIndustrialDigitalOut4.SetResponseExpectedAll(const responseExpected: boolean)

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

procedure TBrickletIndustrialDigitalOut4.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)

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

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: TBrickletIndustrialDigitalOut4; const param: word);
begin
  WriteLn(param);
end;

industrialDigitalOut4.OnExample := {$ifdef FPC}@{$endif}example.MyCallback;

The available callback property and their 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.

property TBrickletIndustrialDigitalOut4.OnMonoflopDone
procedure(sender: TBrickletIndustrialDigitalOut4; const selectionMask: word; const valueMask: word) of object;

This callback is triggered whenever a monoflop timer reaches 0. The parameters contain the involved pins and the current value of the pins (the value after the monoflop).

Constants

const BRICKLET_INDUSTRIAL_DIGITAL_OUT_4_DEVICE_IDENTIFIER

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

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

const BRICKLET_INDUSTRIAL_DIGITAL_OUT_4_DEVICE_DISPLAY_NAME

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