Delphi/Lazarus - OLED 128x64 Bricklet 2.0

This is the description of the Delphi/Lazarus API bindings for the OLED 128x64 Bricklet 2.0. General information and technical specifications for the OLED 128x64 Bricklet 2.0 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).

Hello World

Download (ExampleHelloWorld.pas)

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program ExampleHelloWorld;

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

uses
  SysUtils, IPConnection, BrickletOLED128x64V2;

type
  TExample = class
  private
    ipcon: TIPConnection;
    oled: TBrickletOLED128x64V2;
  public
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; { Change XYZ to the UID of your OLED 128x64 Bricklet 2.0 }

var
  e: TExample;

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

  { Create device object }
  oled := TBrickletOLED128x64V2.Create(UID, ipcon);

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

  { Clear display }
  oled.ClearDisplay;

  { Write "Hello World" starting from upper left corner of the screen }
  oled.WriteLine(0, 0, 'Hello World');

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

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

Pixel Matrix

Download (ExamplePixelMatrix.pas)

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program ExamplePixelMatrix;

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

uses
  Math, SysUtils, IPConnection, BrickletOLED128x64V2;

const
  WIDTH = 128;
  HEIGHT = 64;

type
  TPixels = array [0..(HEIGHT*WIDTH - 1)] of boolean;
  TExample = class
  private
    ipcon: TIPConnection;
    oled: TBrickletOLED128x64V2;
  public
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; { Change XYZ to the UID of your OLED 128x64 Bricklet }

var
  e: TExample;

procedure TExample.Execute;
var row, column: integer; pixels: TPixels;
begin
  { Create IP connection }
  ipcon := TIPConnection.Create;

  { Create device object }
  oled := TBrickletOLED128x64V2.Create(UID, ipcon);

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

  { Clear display }
  oled.ClearDisplay;

  { Draw checkerboard pattern }
  for row := 0 to HEIGHT - 1 do begin
    for column := 0 to WIDTH - 1 do begin
      pixels[row * WIDTH + column] := (row div 8) mod 2 = (column div 8) mod 2;
    end;
  end;

  oled.WritePixels(0, 0, WIDTH-1, HEIGHT-1, pixels);

  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 TBrickletOLED128x64V2.Create(const uid: string; ipcon: TIPConnection)

Creates an object with the unique device ID uid:

oled128x64V2 := TBrickletOLED128x64V2.Create('YOUR_DEVICE_UID', ipcon);

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

procedure TBrickletOLED128x64V2.WritePixelsLowLevel(const xStart: byte; const yStart: byte; const xEnd: byte; const yEnd: byte; const pixelsLength: word; const pixelsChunkOffset: word; const pixelsChunkData: array [0..447] of boolean)

Writes pixels to the specified window.

The x-axis goes from 0 to 127 and the y-axis from 0 to 63. The pixels are written into the window line by line top to bottom and each line is written from left to right.

If automatic draw is enabled (default) the pixels are directly written to the screen. Only pixels that have actually changed are updated on the screen, the rest stays the same.

If automatic draw is disabled the pixels are written to an internal buffer and the buffer is transferred to the display only after DrawBufferedFrame is called. This can be used to avoid flicker when drawing a complex frame in multiple steps.

Automatic draw can be configured with the SetDisplayConfiguration function.

procedure TBrickletOLED128x64V2.ReadPixelsLowLevel(const xStart: byte; const yStart: byte; const xEnd: byte; const yEnd: byte; out pixelsLength: word; out pixelsChunkOffset: word; out pixelsChunkData: array [0..479] of boolean)

Reads pixels from the specified window.

The x-axis goes from 0 to 127 and the y-axis from 0 to 63. The pixels are read from the window line by line top to bottom and each line is read from left to right.

If automatic draw is enabled (default) the pixels that are read are always the same that are shown on the display.

If automatic draw is disabled the pixels are read from the internal buffer (see DrawBufferedFrame).

Automatic draw can be configured with the SetDisplayConfiguration function.

procedure TBrickletOLED128x64V2.ClearDisplay

Clears the complete content of the display.

procedure TBrickletOLED128x64V2.WriteLine(const line: byte; const position: byte; const text: string)

Writes text to a specific line (0 to 7) with a specific position (0 to 21). The text can have a maximum of 22 characters.

For example: (1, 10, "Hello") will write Hello in the middle of the second line of the display.

The display uses a special 5x7 pixel charset. You can view the characters of the charset in Brick Viewer.

procedure TBrickletOLED128x64V2.DrawBufferedFrame(const forceCompleteRedraw: boolean)

Draws the currently buffered frame. Normally each call of WritePixels and WriteLine draws directly onto the display. If you turn automatic draw off (SetDisplayConfiguration), the data is written in an internal buffer and only transferred to the display by calling this function. This can be used to avoid flicker when drawing a complex frame in multiple steps.

Set the force complete redraw to true to redraw the whole display instead of only the changed parts. Normally it should not be necessary to set this to true. It may only become necessary in case of stuck pixels because of errors.

Advanced Functions

procedure TBrickletOLED128x64V2.SetDisplayConfiguration(const contrast: byte; const invert: boolean; const automaticDraw: boolean)

Sets the configuration of the display.

You can set a contrast value from 0 to 255 and you can invert the color (white/black) of the display.

If automatic draw is set to true, the display is automatically updated with every call of WritePixels or WriteLine. If it is set to false, the changes are written into an internal buffer and only shown on the display after a call of DrawBufferedFrame.

The default values are contrast 143, inverting off and automatic draw on.

procedure TBrickletOLED128x64V2.GetDisplayConfiguration(out contrast: byte; out invert: boolean; out automaticDraw: boolean)

Returns the configuration as set by SetDisplayConfiguration.

function TBrickletOLED128x64V2.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 TBrickletOLED128x64V2.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 TBrickletOLED128x64V2.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_OLED_128X64_V2_FUNCTION_WRITE_PIXELS = 1
  • BRICKLET_OLED_128X64_V2_FUNCTION_CLEAR_DISPLAY = 3
  • BRICKLET_OLED_128X64_V2_FUNCTION_SET_DISPLAY_CONFIGURATION = 4
  • BRICKLET_OLED_128X64_V2_FUNCTION_WRITE_LINE = 6
  • BRICKLET_OLED_128X64_V2_FUNCTION_DRAW_BUFFERED_FRAME = 7
  • BRICKLET_OLED_128X64_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BRICKLET_OLED_128X64_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BRICKLET_OLED_128X64_V2_FUNCTION_RESET = 243
  • BRICKLET_OLED_128X64_V2_FUNCTION_WRITE_UID = 248
procedure TBrickletOLED128x64V2.SetResponseExpectedAll(const responseExpected: boolean)

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

procedure TBrickletOLED128x64V2.GetSPITFPErrorCount(out errorCountAckChecksum: longword; out errorCountMessageChecksum: longword; out errorCountFrame: longword; out errorCountOverflow: longword)

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

function TBrickletOLED128x64V2.SetBootloaderMode(const mode: byte): byte

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER = 0
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE = 1
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_STATUS_OK = 0
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_STATUS_INVALID_MODE = 1
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_STATUS_NO_CHANGE = 2
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_STATUS_CRC_MISMATCH = 5
function TBrickletOLED128x64V2.GetBootloaderMode: byte

Returns the current bootloader mode, see SetBootloaderMode.

The following constants are available for this function:

  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER = 0
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE = 1
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BRICKLET_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
procedure TBrickletOLED128x64V2.SetWriteFirmwarePointer(const pointer: longword)

Sets the firmware pointer for WriteFirmware. The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

function TBrickletOLED128x64V2.WriteFirmware(const data: array [0..63] of byte): byte

Writes 64 Bytes of firmware at the position as written by SetWriteFirmwarePointer before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

procedure TBrickletOLED128x64V2.SetStatusLEDConfig(const config: byte)

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_OFF = 0
  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_ON = 1
  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3
function TBrickletOLED128x64V2.GetStatusLEDConfig: byte

Returns the configuration as set by SetStatusLEDConfig

The following constants are available for this function:

  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_OFF = 0
  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_ON = 1
  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BRICKLET_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3
function TBrickletOLED128x64V2.GetChipTemperature: smallint

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

procedure TBrickletOLED128x64V2.Reset

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

procedure TBrickletOLED128x64V2.WriteUID(const uid: longword)

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

function TBrickletOLED128x64V2.ReadUID: longword

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

procedure TBrickletOLED128x64V2.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.

Constants

const BRICKLET_OLED_128X64_V2_DEVICE_IDENTIFIER

This constant is used to identify a OLED 128x64 Bricklet 2.0.

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_OLED_128X64_V2_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a OLED 128x64 Bricklet 2.0.