Delphi/Lazarus - E-Paper 296x128 Bricklet

This is the description of the Delphi/Lazarus API bindings for the E-Paper 296x128 Bricklet. General information and technical specifications for the E-Paper 296x128 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).

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, BrickletEPaper296x128;

type
  TExample = class
  private
    ipcon: TIPConnection;
    ep: TBrickletEPaper296x128;
  public
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; { Change XYZ to the UID of your E-Paper 296x128 Bricklet }

var
  e: TExample;

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

  { Create device object }
  ep := TBrickletEPaper296x128.Create(UID, ipcon);

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

  { Use black background }
  ep.FillDisplay(BRICKLET_E_PAPER_296X128_COLOR_BLACK);

  { Write big white "Hello World" in the middle of the screen }
  ep.DrawText(16, 48, BRICKLET_E_PAPER_296X128_FONT_24X32,
              BRICKLET_E_PAPER_296X128_COLOR_WHITE,
              BRICKLET_E_PAPER_296X128_ORIENTATION_HORIZONTAL, 'Hello World');
  ep.Draw;

  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 TBrickletEPaper296x128.Create(const uid: string; ipcon: TIPConnection)

Creates an object with the unique device ID uid:

ePaper296x128 := TBrickletEPaper296x128.Create('YOUR_DEVICE_UID', ipcon);

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

procedure TBrickletEPaper296x128.Draw

Draws the current black/white and red or gray buffer to the e-paper display.

The Bricklet does not have any double-buffering. You should not call this function while writing to the buffer. See GetDrawStatus.

function TBrickletEPaper296x128.GetDrawStatus: byte

Returns one of three draw statuses:

  • Idle
  • Copying: Data is being copied from the buffer of the Bricklet to the buffer of the display.
  • Drawing: The display is updating its content (during this phase the flickering etc happens).

You can write to the buffer (through one of the write or draw functions) when the status is either idle or drawing. You should not write to the buffer while it is being copied to the display. There is no double-buffering.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_DRAW_STATUS_IDLE = 0
  • BRICKLET_E_PAPER_296X128_DRAW_STATUS_COPYING = 1
  • BRICKLET_E_PAPER_296X128_DRAW_STATUS_DRAWING = 2
procedure TBrickletEPaper296x128.WriteBlackWhite(const xStart: word; const yStart: byte; const xEnd: word; const yEnd: byte; const pixels: array of boolean)

Writes black/white pixels to the specified window into the buffer.

The x-axis goes from 0 to 295 and the y-axis from 0 to 127. The pixels are written into the window line by line top to bottom and each line is written from left to right.

The value 0 (false) corresponds to a black pixel and the value 1 (true) to a white pixel.

This function writes the pixels into the black/white pixel buffer, to draw the buffer to the display use Draw.

Use WriteColor to write red or gray pixels.

function TBrickletEPaper296x128.ReadBlackWhite(const xStart: word; const yStart: byte; const xEnd: word; const yEnd: byte): array of boolean

Returns the current content of the black/white pixel buffer for the specified window.

The x-axis goes from 0 to 295 and the y-axis from 0 to 127. The pixels are written into the window line by line top to bottom and each line is written from left to right.

The current content of the buffer does not have to be the current content of the display. It is possible that the data was not drawn to the display yet and after a restart of the Bricklet the buffer will be reset to black, while the display retains its content.

procedure TBrickletEPaper296x128.WriteColor(const xStart: word; const yStart: byte; const xEnd: word; const yEnd: byte; const pixels: array of boolean)

The E-Paper 296x128 Bricklet is available with the colors black/white/red and black/white/gray. Depending on the model this function writes either red or gray pixels to the specified window into the buffer.

The x-axis goes from 0 to 295 and the y-axis from 0 to 127. The pixels are written into the window line by line top to bottom and each line is written from left to right.

The value 0 (false) means that this pixel does not have color. It will be either black or white (see WriteBlackWhite). The value 1 (true) corresponds to a red or gray pixel, depending on the Bricklet model.

This function writes the pixels into the red or gray pixel buffer, to draw the buffer to the display use Draw.

Use WriteBlackWhite to write black/white pixels.

function TBrickletEPaper296x128.ReadColor(const xStart: word; const yStart: byte; const xEnd: word; const yEnd: byte): array of boolean

Returns the current content of the red or gray pixel buffer for the specified window.

The x-axis goes from 0 to 295 and the y-axis from 0 to 127. The pixels are written into the window line by line top to bottom and each line is written from left to right.

The current content of the buffer does not have to be the current content of the display. It is possible that the data was not drawn to the display yet and after a restart of the Bricklet the buffer will be reset to black, while the display retains its content.

procedure TBrickletEPaper296x128.FillDisplay(const color: byte)

Fills the complete content of the display with the given color.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_COLOR_BLACK = 0
  • BRICKLET_E_PAPER_296X128_COLOR_WHITE = 1
  • BRICKLET_E_PAPER_296X128_COLOR_RED = 2
  • BRICKLET_E_PAPER_296X128_COLOR_GRAY = 2
procedure TBrickletEPaper296x128.DrawText(const positionX: word; const positionY: byte; const font: byte; const color: byte; const orientation: byte; const text: string)

Draws a text with up to 50 characters at the pixel position (x, y).

The x values have to be within the range of 0 to 295 and the y values have to be within the range of 0 to 127.

You can use one of 9 different font sizes and draw the text in black/white/red|gray. The text can be drawn horizontal or vertical.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_FONT_6X8 = 0
  • BRICKLET_E_PAPER_296X128_FONT_6X16 = 1
  • BRICKLET_E_PAPER_296X128_FONT_6X24 = 2
  • BRICKLET_E_PAPER_296X128_FONT_6X32 = 3
  • BRICKLET_E_PAPER_296X128_FONT_12X16 = 4
  • BRICKLET_E_PAPER_296X128_FONT_12X24 = 5
  • BRICKLET_E_PAPER_296X128_FONT_12X32 = 6
  • BRICKLET_E_PAPER_296X128_FONT_18X24 = 7
  • BRICKLET_E_PAPER_296X128_FONT_18X32 = 8
  • BRICKLET_E_PAPER_296X128_FONT_24X32 = 9
  • BRICKLET_E_PAPER_296X128_COLOR_BLACK = 0
  • BRICKLET_E_PAPER_296X128_COLOR_WHITE = 1
  • BRICKLET_E_PAPER_296X128_COLOR_RED = 2
  • BRICKLET_E_PAPER_296X128_COLOR_GRAY = 2
  • BRICKLET_E_PAPER_296X128_ORIENTATION_HORIZONTAL = 0
  • BRICKLET_E_PAPER_296X128_ORIENTATION_VERTICAL = 1
procedure TBrickletEPaper296x128.DrawLine(const positionXStart: word; const positionYStart: byte; const positionXEnd: word; const positionYEnd: byte; const color: byte)

Draws a line from (x, y)-start to (x, y)-end in the given color. The x values have to be within the range of 0 to 295 and the y values have t be within the range of 0 to 127.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_COLOR_BLACK = 0
  • BRICKLET_E_PAPER_296X128_COLOR_WHITE = 1
  • BRICKLET_E_PAPER_296X128_COLOR_RED = 2
  • BRICKLET_E_PAPER_296X128_COLOR_GRAY = 2
procedure TBrickletEPaper296x128.DrawBox(const positionXStart: word; const positionYStart: byte; const positionXEnd: word; const positionYEnd: byte; const fill: boolean; const color: byte)

Draws a box from (x, y)-start to (x, y)-end in the given color. The x values have to be within the range of 0 to 295 and the y values have to be within the range of 0 to 127.

If you set fill to true, the box will be filled with the color. Otherwise only the outline will be drawn.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_COLOR_BLACK = 0
  • BRICKLET_E_PAPER_296X128_COLOR_WHITE = 1
  • BRICKLET_E_PAPER_296X128_COLOR_RED = 2
  • BRICKLET_E_PAPER_296X128_COLOR_GRAY = 2

Advanced Functions

procedure TBrickletEPaper296x128.SetUpdateMode(const updateMode: byte)

Note

The default update mode corresponds to the default e-paper display manufacturer settings. All of the other modes are experimental and will result in increased ghosting and possibly other long-term side effects.

If you want to know more about the inner workings of an e-paper display take a look at this excellent video from Ben Krasnow: https://www.youtube.com/watch?v=MsbiO8EAsGw.

If you are not sure about this option, leave the update mode at default.

Currently there are three update modes available:

  • Default: Settings as given by the manufacturer. An update will take about 7.5 seconds and during the update the screen will flicker several times.
  • Black/White: This will only update the black/white pixel. It uses the manufacturer settings for black/white and ignores the red or gray pixel buffer. With this mode the display will flicker once and it takes about 2.5 seconds. Compared to the default settings there is more ghosting.
  • Delta: This will only update the black/white pixel. It uses an aggressive method where the changes are not applied for a whole buffer but only for the delta between the last and the next buffer. With this mode the display will not flicker during an update and it takes about 900-950ms. Compared to the other two settings there is more ghosting. This mode can be used for something like a flicker-free live update of a text.

With the black/white/red display if you use either the black/white or the delta mode, after a while of going back and forth between black and white the white color will start to appear red-ish or pink-ish.

If you use the aggressive delta mode and rapidly change the content, we recommend that you change back to the default mode every few hours and in the default mode cycle between the three available colors a few times. This will get rid of the ghosting and after that you can go back to the delta mode with flicker-free updates.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_UPDATE_MODE_DEFAULT = 0
  • BRICKLET_E_PAPER_296X128_UPDATE_MODE_BLACK_WHITE = 1
  • BRICKLET_E_PAPER_296X128_UPDATE_MODE_DELTA = 2
function TBrickletEPaper296x128.GetUpdateMode: byte

Returns the update mode as set by SetUpdateMode.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_UPDATE_MODE_DEFAULT = 0
  • BRICKLET_E_PAPER_296X128_UPDATE_MODE_BLACK_WHITE = 1
  • BRICKLET_E_PAPER_296X128_UPDATE_MODE_DELTA = 2
procedure TBrickletEPaper296x128.SetDisplayType(const displayType: byte)

Sets the type of the display. The e-paper display is available in black/white/red and black/white/gray. This will be factory set during the flashing and testing phase. The value is saved in non-volatile memory and will stay after a power cycle.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_RED = 0
  • BRICKLET_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_GRAY = 1
function TBrickletEPaper296x128.GetDisplayType: byte

Returns the type of the e-paper display. It can either be black/white/red or black/white/gray.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_RED = 0
  • BRICKLET_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_GRAY = 1
function TBrickletEPaper296x128.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 TBrickletEPaper296x128.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.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW = 1
  • BRICKLET_E_PAPER_296X128_FUNCTION_WRITE_BLACK_WHITE = 3
  • BRICKLET_E_PAPER_296X128_FUNCTION_WRITE_COLOR = 5
  • BRICKLET_E_PAPER_296X128_FUNCTION_FILL_DISPLAY = 7
  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW_TEXT = 8
  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW_LINE = 9
  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW_BOX = 10
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_UPDATE_MODE = 12
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_DISPLAY_TYPE = 14
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BRICKLET_E_PAPER_296X128_FUNCTION_RESET = 243
  • BRICKLET_E_PAPER_296X128_FUNCTION_WRITE_UID = 248
procedure TBrickletEPaper296x128.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 constants are available for this function:

  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW = 1
  • BRICKLET_E_PAPER_296X128_FUNCTION_WRITE_BLACK_WHITE = 3
  • BRICKLET_E_PAPER_296X128_FUNCTION_WRITE_COLOR = 5
  • BRICKLET_E_PAPER_296X128_FUNCTION_FILL_DISPLAY = 7
  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW_TEXT = 8
  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW_LINE = 9
  • BRICKLET_E_PAPER_296X128_FUNCTION_DRAW_BOX = 10
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_UPDATE_MODE = 12
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_DISPLAY_TYPE = 14
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BRICKLET_E_PAPER_296X128_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BRICKLET_E_PAPER_296X128_FUNCTION_RESET = 243
  • BRICKLET_E_PAPER_296X128_FUNCTION_WRITE_UID = 248
procedure TBrickletEPaper296x128.SetResponseExpectedAll(const responseExpected: boolean)

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

procedure TBrickletEPaper296x128.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 TBrickletEPaper296x128.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_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER = 0
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE = 1
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_STATUS_OK = 0
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_STATUS_INVALID_MODE = 1
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_STATUS_NO_CHANGE = 2
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_STATUS_CRC_MISMATCH = 5
function TBrickletEPaper296x128.GetBootloaderMode: byte

Returns the current bootloader mode, see SetBootloaderMode.

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER = 0
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE = 1
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BRICKLET_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
procedure TBrickletEPaper296x128.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 TBrickletEPaper296x128.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 TBrickletEPaper296x128.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_E_PAPER_296X128_STATUS_LED_CONFIG_OFF = 0
  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_ON = 1
  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_STATUS = 3
function TBrickletEPaper296x128.GetStatusLEDConfig: byte

Returns the configuration as set by SetStatusLEDConfig

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_OFF = 0
  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_ON = 1
  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BRICKLET_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_STATUS = 3
function TBrickletEPaper296x128.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 TBrickletEPaper296x128.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 TBrickletEPaper296x128.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 TBrickletEPaper296x128.ReadUID: longword

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

procedure TBrickletEPaper296x128.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.

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: TBrickletEPaper296x128; const param: word);
begin
  WriteLn(param);
end;

ePaper296x128.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 TBrickletEPaper296x128.OnDrawStatus
procedure(sender: TBrickletEPaper296x128; const drawStatus: byte) of object;

Callback for the current draw status. Will be called every time the draw status changes (see GetDrawStatus).

The following constants are available for this function:

  • BRICKLET_E_PAPER_296X128_DRAW_STATUS_IDLE = 0
  • BRICKLET_E_PAPER_296X128_DRAW_STATUS_COPYING = 1
  • BRICKLET_E_PAPER_296X128_DRAW_STATUS_DRAWING = 2

Constants

const BRICKLET_E_PAPER_296X128_DEVICE_IDENTIFIER

This constant is used to identify a E-Paper 296x128 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_E_PAPER_296X128_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a E-Paper 296x128 Bricklet.