This is the description of the Java 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 Java API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
Download (ExampleHelloWorld.java)
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 | import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletEPaper296x128;
public class ExampleHelloWorld {
private static final String HOST = "localhost";
private static final int PORT = 4223;
// Change XYZ to the UID of your E-Paper 296x128 Bricklet
private static final String UID = "XYZ";
// Note: To make the example code cleaner we do not handle exceptions. Exceptions
// you might normally want to catch are described in the documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletEPaper296x128 ep = new BrickletEPaper296x128(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Use black background
ep.fillDisplay(BrickletEPaper296x128.COLOR_BLACK);
// Write big white "Hello World" in the middle of the screen
ep.drawText(16, 48, BrickletEPaper296x128.FONT_24X32,
BrickletEPaper296x128.COLOR_WHITE,
BrickletEPaper296x128.ORIENTATION_HORIZONTAL, "Hello World");
ep.draw();
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
|
Download (ExampleLoadImage.java)
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 | import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.File;
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletEPaper296x128;
public class ExampleLoadImage {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "XZY"; // Change XYZ to the UID of your E-Paper 296x128 Bricklet
private static final short WIDTH = 296;
private static final short HEIGHT = 128;
static boolean[] boolArrayFromImage(BufferedImage image, int color) throws Exception {
boolean[] pixels = new boolean[HEIGHT * WIDTH];
short h, w;
for (h = 0; h < HEIGHT; h++) {
for (w = 0; w < WIDTH; w++) {
pixels[h*WIDTH + w] = ((image.getRGB(w, h) & 0x00FFFFFF) == color);
}
}
return pixels;
}
// Note: To make the example code cleaner we do not handle exceptions. Exceptions
// you might normally want to catch are described in the documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletEPaper296x128 epaper = new BrickletEPaper296x128(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Download example image here:
// https://raw.githubusercontent.com/Tinkerforge/e-paper-296x128-bricklet/master/software/examples/tf_red.png
BufferedImage image = ImageIO.read(new File("tf_red.png"));
// Get black/white pixels from image and write them to the Bricklet buffer
boolean[] pixelsBW = boolArrayFromImage(image, 0xFFFFFF);
epaper.writeBlackWhite(0, 0, WIDTH-1, HEIGHT-1, pixelsBW);
// Get red pixels from image and write them to the Bricklet buffer
boolean[] pixelsRed = boolArrayFromImage(image, 0xFF0000);
epaper.writeColor(0, 0, WIDTH-1, HEIGHT-1, pixelsRed);
// Draw buffered values to the display
epaper.draw();
}
}
|
Generally, every method of the Java bindings that returns a value can
throw a TimeoutException
. This exception gets thrown if the
device did not respond. If a cable based connection is used, it is
unlikely that this exception gets thrown (assuming nobody unplugs the
device). However, if a wireless connection is used, timeouts will occur
if the distance to the device gets too big.
Beside the TimeoutException
there is also a NotConnectedException
that
is thrown if a method needs to communicate with the device while the
IP Connection is not connected.
Since Java does not support multiple return values and return by reference is not possible for primitive types, we use small classes that only consist of member variables. The member variables of the returned objects are described in the corresponding method descriptions.
The package for all Brick/Bricklet bindings and the IP Connection is
com.tinkerforge.*
All methods listed below are thread-safe.
BrickletEPaper296x128
(String uid, IPConnection ipcon)¶Parameters: |
|
---|---|
Returns: |
|
Creates an object with the unique device ID uid
:
BrickletEPaper296x128 ePaper296x128 = new BrickletEPaper296x128("YOUR_DEVICE_UID", ipcon);
This object can then be used after the IP Connection is connected.
BrickletEPaper296x128.
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()
.
BrickletEPaper296x128.
getDrawStatus
()¶Returns: |
|
---|
Returns one of three draw statuses:
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:
For drawStatus:
BrickletEPaper296x128.
writeBlackWhite
(int xStart, int yStart, int xEnd, int yEnd, boolean[] pixels)¶Parameters: |
|
---|
Writes black/white pixels to the specified window into the buffer.
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.
BrickletEPaper296x128.
readBlackWhite
(int xStart, int yStart, int xEnd, int yEnd)¶Parameters: |
|
---|---|
Returns: |
|
Returns the current content of the black/white pixel buffer for the specified window.
The pixels are read into the window line by line top to bottom and each line is read 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.
BrickletEPaper296x128.
writeColor
(int xStart, int yStart, int xEnd, int yEnd, boolean[] pixels)¶Parameters: |
|
---|
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 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.
BrickletEPaper296x128.
readColor
(int xStart, int yStart, int xEnd, int yEnd)¶Parameters: |
|
---|---|
Returns: |
|
Returns the current content of the red or gray pixel buffer for the specified window.
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.
BrickletEPaper296x128.
fillDisplay
(int color)¶Parameters: |
|
---|
Fills the complete content of the display with the given color.
This function writes the pixels into the black/white/red|gray pixel buffer, to draw the buffer
to the display use draw()
.
The following constants are available for this function:
For color:
BrickletEPaper296x128.
drawText
(int positionX, int positionY, int font, int color, int orientation, String text)¶Parameters: |
|
---|
Draws a text with up to 50 characters at the pixel position (x, y).
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.
This function writes the pixels into the black/white/red|gray pixel buffer, to draw the buffer
to the display use draw()
.
The font conforms to code page 437.
The following constants are available for this function:
For font:
For color:
For orientation:
BrickletEPaper296x128.
drawLine
(int positionXStart, int positionYStart, int positionXEnd, int positionYEnd, int color)¶Parameters: |
|
---|
Draws a line from (x, y)-start to (x, y)-end in the given color.
This function writes the pixels into the black/white/red|gray pixel buffer, to draw the buffer
to the display use draw()
.
The following constants are available for this function:
For color:
BrickletEPaper296x128.
drawBox
(int positionXStart, int positionYStart, int positionXEnd, int positionYEnd, boolean fill, int color)¶Parameters: |
|
---|
Draws a box from (x, y)-start to (x, y)-end in the given color.
If you set fill to true, the box will be filled with the color. Otherwise only the outline will be drawn.
This function writes the pixels into the black/white/red|gray pixel buffer, to draw the buffer
to the display use draw()
.
The following constants are available for this function:
For color:
BrickletEPaper296x128.
setUpdateMode
(int updateMode)¶Parameters: |
|
---|
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:
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:
For updateMode:
BrickletEPaper296x128.
getUpdateMode
()¶Returns: |
|
---|
Returns the update mode as set by setUpdateMode()
.
The following constants are available for this function:
For updateMode:
BrickletEPaper296x128.
setDisplayType
(int displayType)¶Parameters: |
|
---|
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:
For displayType:
BrickletEPaper296x128.
getDisplayType
()¶Returns: |
|
---|
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:
For displayType:
BrickletEPaper296x128.
setDisplayDriver
(int displayDriver)¶Parameters: |
|
---|
Sets the type of display driver. The Bricklet can currently support SSD1675A and SSD1680. 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:
For displayDriver:
New in version 2.0.3 (Plugin).
BrickletEPaper296x128.
getDisplayDriver
()¶Returns: |
|
---|
Returns the e-paper display driver.
The following constants are available for this function:
For displayDriver:
New in version 2.0.3 (Plugin).
BrickletEPaper296x128.
getSPITFPErrorCount
()¶Return Object: |
|
---|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
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.
BrickletEPaper296x128.
setStatusLEDConfig
(int config)¶Parameters: |
|
---|
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:
For config:
BrickletEPaper296x128.
getStatusLEDConfig
()¶Returns: |
|
---|
Returns the configuration as set by setStatusLEDConfig()
The following constants are available for this function:
For config:
BrickletEPaper296x128.
getChipTemperature
()¶Returns: |
|
---|
Returns the temperature 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.
BrickletEPaper296x128.
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!
BrickletEPaper296x128.
getIdentity
()¶Return Object: |
|
---|
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.
Listeners can be registered to receive
time critical or recurring data from the device. The registration is done
with add*Listener()
functions of the device object.
The parameter is a listener class object, for example:
device.addExampleListener(new BrickletEPaper296x128.ExampleListener() {
public void property(int value) {
System.out.println("Value: " + value);
}
});
The available listener classes with inherent methods to be overwritten
are described below. It is possible to add several listeners and
to remove them with the corresponding remove*Listener()
function.
Note
Using listeners 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.
BrickletEPaper296x128.
DrawStatusListener
()¶This listener can be added with the addDrawStatusListener()
function.
An added listener can be removed with the removeDrawStatusListener()
function.
drawStatus
(int drawStatus)Parameters: |
|
---|
Listener for the current draw status. Will be called every time the
draw status changes (see getDrawStatus()
).
The following constants are available for this function:
For drawStatus:
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.
BrickletEPaper296x128.
getAPIVersion
()¶Return Object: |
|
---|
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.
BrickletEPaper296x128.
getResponseExpected
(byte functionId)¶Parameters: |
|
---|---|
Returns: |
|
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 listener 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:
BrickletEPaper296x128.
setResponseExpected
(byte functionId, boolean responseExpected)¶Parameters: |
|
---|
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 listener 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:
BrickletEPaper296x128.
setResponseExpectedAll
(boolean responseExpected)¶Parameters: |
|
---|
Changes the response expected flag for all setter and listener configuration functions of this device at once.
Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.
BrickletEPaper296x128.
setBootloaderMode
(int mode)¶Parameters: |
|
---|---|
Returns: |
|
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:
For mode:
For status:
BrickletEPaper296x128.
getBootloaderMode
()¶Returns: |
|
---|
Returns the current bootloader mode, see setBootloaderMode()
.
The following constants are available for this function:
For mode:
BrickletEPaper296x128.
setWriteFirmwarePointer
(long pointer)¶Parameters: |
|
---|
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.
BrickletEPaper296x128.
writeFirmware
(int[] data)¶Parameters: |
|
---|---|
Returns: |
|
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.
BrickletEPaper296x128.
writeUID
(long uid)¶Parameters: |
|
---|
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.
BrickletEPaper296x128.
readUID
()¶Returns: |
|
---|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
BrickletEPaper296x128.
DEVICE_IDENTIFIER
¶This constant is used to identify a E-Paper 296x128 Bricklet.
The getIdentity()
function and the
IPConnection.EnumerateListener
listener of the IP Connection have a deviceIdentifier
parameter to specify
the Brick's or Bricklet's type.
BrickletEPaper296x128.
DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a E-Paper 296x128 Bricklet.