Software / API Bindings / Go / API Reference and Examples / Bricklets / E-Paper 296x128 Bricklet

Go - E-Paper 296x128 Bricklet¶

This is the description of the Go 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 Go API bindings is part of their general description. Additional documentation can be found on godoc.org.

Examples¶

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

Hello World¶

Download (example_hello_world.go)

package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/e_paper_296x128_bricklet"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your E-Paper 296x128 Bricklet.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    ep, _ := e_paper_296x128_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // Don't use device before ipcon is connected.

    // Use black background
    ep.FillDisplay(e_paper_296x128_bricklet.ColorBlack)

    // Write big white "Hello World" in the middle of the screen
    ep.DrawText(16, 48, e_paper_296x128_bricklet.Font24x32,
        e_paper_296x128_bricklet.ColorWhite,
        e_paper_296x128_bricklet.OrientationHorizontal, "Hello World")
    ep.Draw()

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

Load Image¶

Download (example_load_image.go)

package main

import (
    "fmt"
    "os"
    "image"
    "image/png"
    "github.com/Tinkerforge/go-api-bindings/e_paper_296x128_bricklet"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your E-Paper 296x128 Bricklet.
const WIDTH = 296
const HEIGHT = 128

// Convert Image to matching color bool array
func BoolArrayFromImage(image image.Image, r uint32, g uint32, b uint32) ([]bool, error) {
    var pixels []bool
    for row := 0; row < HEIGHT; row++ {
        for column := 0; column < WIDTH; column++ {
            rCmp, gCmp, bCmp, _ := image.At(column, row).RGBA();
            pixels = append(pixels, (rCmp == r) && (gCmp == g) && (bCmp == b))
        }
    }

    return pixels, nil
}

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    ep, _ := e_paper_296x128_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // 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
    image.RegisterFormat("png", "png", png.Decode, png.DecodeConfig)
    file, _ := os.Open("tf_red.png")
    defer file.Close()
    image, _, _ := image.Decode(file)

    // Get black/white pixels from image and write them to the Bricklet buffer
    pixelsBW, _ := BoolArrayFromImage(image, 0xFFFF, 0xFFFF, 0xFFFF)
    ep.WriteBlackWhite(0, 0, WIDTH-1, HEIGHT-1, pixelsBW)

    // Get red pixels from image and write them to the Bricklet buffer
    pixelsRed, _ := BoolArrayFromImage(image, 0xFFFF, 0, 0)
    ep.WriteColor(0, 0, WIDTH-1, HEIGHT-1, pixelsRed)

    // Draw buffered values to the display
    ep.Draw()

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

API¶

The E-Paper 296x128 Bricklet API is defined in the package github.com/Tinkerforge/go-api-bindings/e_paper_296x128_bricklet

Nearly every function of the Go bindings can return an ipconnection.DeviceError, implementing the error interface. The error can have one of the following values:

ipconnection.DeviceErrorSuccess = 0
ipconnection.DeviceErrorInvalidParameter = 1
ipconnection.DeviceErrorFunctionNotSupported = 2
ipconnection.DeviceErrorUnknownError = 3

which correspond to the values returned from Bricks and Bricklets.

All functions listed below are thread-safe.

Basic Functions¶

func e_paper_296x128_bricklet.New(uid string, ipcon *IPConnection) (device EPaper296x128Bricklet, err error)¶

Parameters:	uid – Type: string ipcon – Type: *IPConnection
Returns:	device – Type: EPaper296x128Bricklet err – Type: error

Creates a new EPaper296x128Bricklet object with the unique device ID uid and adds it to the IPConnection ipcon:

device, err := e_paper_296x128_bricklet.New("YOUR_DEVICE_UID", &ipcon)

This device object can be used after the IPConnection has been connected.

func (*EPaper296x128Bricklet) Draw() (err error)¶

Returns:	err – Type: error

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().

func (*EPaper296x128Bricklet) GetDrawStatus() (drawStatus uint8, err error)¶

Returns:	drawStatus – Type: uint8, Range: See constants err – Type: error

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:

For drawStatus:

e_paper_296x128_bricklet.DrawStatusIdle = 0
e_paper_296x128_bricklet.DrawStatusCopying = 1
e_paper_296x128_bricklet.DrawStatusDrawing = 2

func (*EPaper296x128Bricklet) WriteBlackWhite(xStart uint16, yStart uint8, xEnd uint16, yEnd uint8, pixels []bool) (err error)¶

Parameters:	xStart – Type: uint16, Range: [0 to 295] yStart – Type: uint8, Range: [0 to 127] xEnd – Type: uint16, Range: [0 to 295] yEnd – Type: uint8, Range: [0 to 127] pixels – Type: []bool, Length: variable
Returns:	err – Type: error

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.

func (*EPaper296x128Bricklet) ReadBlackWhite(xStart uint16, yStart uint8, xEnd uint16, yEnd uint8) (pixels []bool, err error)¶

Parameters:	xStart – Type: uint16, Range: [0 to 295] yStart – Type: uint8, Range: [0 to 127] xEnd – Type: uint16, Range: [0 to 295] yEnd – Type: uint8, Range: [0 to 127]
Returns:	pixels – Type: []bool, Length: variable err – Type: error

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.

func (*EPaper296x128Bricklet) WriteColor(xStart uint16, yStart uint8, xEnd uint16, yEnd uint8, pixels []bool) (err error)¶

Parameters:	xStart – Type: uint16, Range: [0 to 295] yStart – Type: uint8, Range: [0 to 127] xEnd – Type: uint16, Range: [0 to 295] yEnd – Type: uint8, Range: [0 to 127] pixels – Type: []bool, Length: variable
Returns:	err – Type: error

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.

func (*EPaper296x128Bricklet) ReadColor(xStart uint16, yStart uint8, xEnd uint16, yEnd uint8) (pixels []bool, err error)¶

Parameters:	xStart – Type: uint16, Range: [0 to 295] yStart – Type: uint8, Range: [0 to 127] xEnd – Type: uint16, Range: [0 to 295] yEnd – Type: uint8, Range: [0 to 127]
Returns:	pixels – Type: []bool, Length: variable err – Type: error

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.

func (*EPaper296x128Bricklet) FillDisplay(color uint8) (err error)¶

Parameters:	color – Type: uint8, Range: See constants
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.ColorBlack = 0
e_paper_296x128_bricklet.ColorWhite = 1
e_paper_296x128_bricklet.ColorRed = 2
e_paper_296x128_bricklet.ColorGray = 2

func (*EPaper296x128Bricklet) DrawText(positionX uint16, positionY uint8, font uint8, color uint8, orientation uint8, text string) (err error)¶

Parameters:	positionX – Type: uint16, Range: [0 to 295] positionY – Type: uint8, Range: [0 to 127] font – Type: uint8, Range: See constants color – Type: uint8, Range: See constants orientation – Type: uint8, Range: See constants text – Type: string, Length: up to 50
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.Font6x8 = 0
e_paper_296x128_bricklet.Font6x16 = 1
e_paper_296x128_bricklet.Font6x24 = 2
e_paper_296x128_bricklet.Font6x32 = 3
e_paper_296x128_bricklet.Font12x16 = 4
e_paper_296x128_bricklet.Font12x24 = 5
e_paper_296x128_bricklet.Font12x32 = 6
e_paper_296x128_bricklet.Font18x24 = 7
e_paper_296x128_bricklet.Font18x32 = 8
e_paper_296x128_bricklet.Font24x32 = 9

For color:

e_paper_296x128_bricklet.ColorBlack = 0
e_paper_296x128_bricklet.ColorWhite = 1
e_paper_296x128_bricklet.ColorRed = 2
e_paper_296x128_bricklet.ColorGray = 2

For orientation:

e_paper_296x128_bricklet.OrientationHorizontal = 0
e_paper_296x128_bricklet.OrientationVertical = 1

func (*EPaper296x128Bricklet) DrawLine(positionXStart uint16, positionYStart uint8, positionXEnd uint16, positionYEnd uint8, color uint8) (err error)¶

Parameters:	positionXStart – Type: uint16, Range: [0 to 295] positionYStart – Type: uint8, Range: [0 to 127] positionXEnd – Type: uint16, Range: [0 to 295] positionYEnd – Type: uint8, Range: [0 to 127] color – Type: uint8, Range: See constants
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.ColorBlack = 0
e_paper_296x128_bricklet.ColorWhite = 1
e_paper_296x128_bricklet.ColorRed = 2
e_paper_296x128_bricklet.ColorGray = 2

func (*EPaper296x128Bricklet) DrawBox(positionXStart uint16, positionYStart uint8, positionXEnd uint16, positionYEnd uint8, fill bool, color uint8) (err error)¶

Parameters:	positionXStart – Type: uint16, Range: [0 to 295] positionYStart – Type: uint8, Range: [0 to 127] positionXEnd – Type: uint16, Range: [0 to 295] positionYEnd – Type: uint8, Range: [0 to 127] fill – Type: bool color – Type: uint8, Range: See constants
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.ColorBlack = 0
e_paper_296x128_bricklet.ColorWhite = 1
e_paper_296x128_bricklet.ColorRed = 2
e_paper_296x128_bricklet.ColorGray = 2

Advanced Functions¶

func (*EPaper296x128Bricklet) SetUpdateMode(updateMode uint8) (err error)¶

Parameters:	updateMode – Type: uint8, Range: See constants, Default: 0
Returns:	err – Type: error

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:

For updateMode:

e_paper_296x128_bricklet.UpdateModeDefault = 0
e_paper_296x128_bricklet.UpdateModeBlackWhite = 1
e_paper_296x128_bricklet.UpdateModeDelta = 2

func (*EPaper296x128Bricklet) GetUpdateMode() (updateMode uint8, err error)¶

Returns:	updateMode – Type: uint8, Range: See constants, Default: 0 err – Type: error

Returns the update mode as set by SetUpdateMode().

The following constants are available for this function:

For updateMode:

e_paper_296x128_bricklet.UpdateModeDefault = 0
e_paper_296x128_bricklet.UpdateModeBlackWhite = 1
e_paper_296x128_bricklet.UpdateModeDelta = 2

func (*EPaper296x128Bricklet) SetDisplayType(displayType uint8) (err error)¶

Parameters:	displayType – Type: uint8, Range: See constants
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.DisplayTypeBlackWhiteRed = 0
e_paper_296x128_bricklet.DisplayTypeBlackWhiteGray = 1

func (*EPaper296x128Bricklet) GetDisplayType() (displayType uint8, err error)¶

Returns:	displayType – Type: uint8, Range: See constants err – Type: error

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:

e_paper_296x128_bricklet.DisplayTypeBlackWhiteRed = 0
e_paper_296x128_bricklet.DisplayTypeBlackWhiteGray = 1

func (*EPaper296x128Bricklet) SetDisplayDriver(displayDriver uint8) (err error)¶

Parameters:	displayDriver – Type: uint8, Range: See constants
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.DisplayDriverSSD1675A = 0
e_paper_296x128_bricklet.DisplayDriverSSD1680 = 1

New in version 2.0.3 (Plugin).

func (*EPaper296x128Bricklet) GetDisplayDriver() (displayDriver uint8, err error)¶

Returns:	displayDriver – Type: uint8, Range: See constants err – Type: error

Returns the e-paper display driver.

The following constants are available for this function:

For displayDriver:

e_paper_296x128_bricklet.DisplayDriverSSD1675A = 0
e_paper_296x128_bricklet.DisplayDriverSSD1680 = 1

New in version 2.0.3 (Plugin).

func (*EPaper296x128Bricklet) GetSPITFPErrorCount() (errorCountAckChecksum uint32, errorCountMessageChecksum uint32, errorCountFrame uint32, errorCountOverflow uint32, err error)¶

Returns:	errorCountAckChecksum – Type: uint32, Range: [0 to 2³² - 1] errorCountMessageChecksum – Type: uint32, Range: [0 to 2³² - 1] errorCountFrame – Type: uint32, Range: [0 to 2³² - 1] errorCountOverflow – Type: uint32, Range: [0 to 2³² - 1] err – Type: error

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.

func (*EPaper296x128Bricklet) SetStatusLEDConfig(config uint8) (err error)¶

Parameters:	config – Type: uint8, Range: See constants, Default: 3
Returns:	err – Type: error

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:

e_paper_296x128_bricklet.StatusLEDConfigOff = 0
e_paper_296x128_bricklet.StatusLEDConfigOn = 1
e_paper_296x128_bricklet.StatusLEDConfigShowHeartbeat = 2
e_paper_296x128_bricklet.StatusLEDConfigShowStatus = 3

func (*EPaper296x128Bricklet) GetStatusLEDConfig() (config uint8, err error)¶

Returns:	config – Type: uint8, Range: See constants, Default: 3 err – Type: error

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

For config:

e_paper_296x128_bricklet.StatusLEDConfigOff = 0
e_paper_296x128_bricklet.StatusLEDConfigOn = 1
e_paper_296x128_bricklet.StatusLEDConfigShowHeartbeat = 2
e_paper_296x128_bricklet.StatusLEDConfigShowStatus = 3

func (*EPaper296x128Bricklet) GetChipTemperature() (temperature int16, err error)¶

Returns:	temperature – Type: int16, Unit: 1 °C, Range: [-2¹⁵ to 2¹⁵ - 1] err – Type: error

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.

func (*EPaper296x128Bricklet) Reset() (err error)¶

Returns:	err – Type: error

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!

func (*EPaper296x128Bricklet) GetIdentity() (uid string, connectedUid string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, err error)¶

Returns:

Returns:	uid – Type: string, Length: up to 8 connectedUid – Type: string, Length: up to 8 position – Type: rune, Range: ['a' to 'h', 'z'] hardwareVersion – Type: [3]uint8 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] firmwareVersion – Type: [3]uint8 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] deviceIdentifier – Type: uint16, Range: [0 to 2¹⁶ - 1] err – Type: error

uid – Type: string, Length: up to 8
connectedUid – Type: string, Length: up to 8
position – Type: rune, Range: ['a' to 'h', 'z']
hardwareVersion – Type: [3]uint8

0: major – Type: uint8, Range: [0 to 255]
1: minor – Type: uint8, Range: [0 to 255]
2: revision – Type: uint8, Range: [0 to 255]

firmwareVersion – Type: [3]uint8

0: major – Type: uint8, Range: [0 to 255]
1: minor – Type: uint8, Range: [0 to 255]
2: revision – Type: uint8, Range: [0 to 255]

deviceIdentifier – Type: uint16, Range: [0 to 2¹⁶ - 1]
err – Type: error

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.

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding Register*Callback function, which returns a unique callback ID. This ID can be used to deregister the callback later with the corresponding Deregister*Callback function.

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.

func (*EPaper296x128Bricklet) RegisterDrawStatusCallback(func(drawStatus uint8)) (registrationId uint64)¶

Callback Parameters:	drawStatus – Type: uint8, Range: See constants
Returns:	registrationId – Type: uint64

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:

For drawStatus:

e_paper_296x128_bricklet.DrawStatusIdle = 0
e_paper_296x128_bricklet.DrawStatusCopying = 1
e_paper_296x128_bricklet.DrawStatusDrawing = 2

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.

func (*EPaper296x128Bricklet) GetAPIVersion() (apiVersion [3]uint8, err error)¶

Returns:	apiVersion – Type: [3]uint8 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] err – Type: error

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.

func (*EPaper296x128Bricklet) GetResponseExpected(functionId uint8) (responseExpected bool, err error)¶

Parameters:	functionId – Type: uint8, Range: See constants
Returns:	responseExpected – Type: bool err – Type: error

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:

e_paper_296x128_bricklet.FunctionDraw = 1
e_paper_296x128_bricklet.FunctionWriteBlackWhite = 3
e_paper_296x128_bricklet.FunctionWriteColor = 5
e_paper_296x128_bricklet.FunctionFillDisplay = 7
e_paper_296x128_bricklet.FunctionDrawText = 8
e_paper_296x128_bricklet.FunctionDrawLine = 9
e_paper_296x128_bricklet.FunctionDrawBox = 10
e_paper_296x128_bricklet.FunctionSetUpdateMode = 12
e_paper_296x128_bricklet.FunctionSetDisplayType = 14
e_paper_296x128_bricklet.FunctionSetDisplayDriver = 16
e_paper_296x128_bricklet.FunctionSetWriteFirmwarePointer = 237
e_paper_296x128_bricklet.FunctionSetStatusLEDConfig = 239
e_paper_296x128_bricklet.FunctionReset = 243
e_paper_296x128_bricklet.FunctionWriteUID = 248

func (*EPaper296x128Bricklet) SetResponseExpected(functionId uint8, responseExpected bool) (err error)¶

Parameters:	functionId – Type: uint8, Range: See constants responseExpected – Type: bool
Returns:	err – Type: error

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.

The following constants are available for this function:

For functionId:

e_paper_296x128_bricklet.FunctionDraw = 1
e_paper_296x128_bricklet.FunctionWriteBlackWhite = 3
e_paper_296x128_bricklet.FunctionWriteColor = 5
e_paper_296x128_bricklet.FunctionFillDisplay = 7
e_paper_296x128_bricklet.FunctionDrawText = 8
e_paper_296x128_bricklet.FunctionDrawLine = 9
e_paper_296x128_bricklet.FunctionDrawBox = 10
e_paper_296x128_bricklet.FunctionSetUpdateMode = 12
e_paper_296x128_bricklet.FunctionSetDisplayType = 14
e_paper_296x128_bricklet.FunctionSetDisplayDriver = 16
e_paper_296x128_bricklet.FunctionSetWriteFirmwarePointer = 237
e_paper_296x128_bricklet.FunctionSetStatusLEDConfig = 239
e_paper_296x128_bricklet.FunctionReset = 243
e_paper_296x128_bricklet.FunctionWriteUID = 248

func (*EPaper296x128Bricklet) SetResponseExpectedAll(responseExpected bool) (err error)¶

Parameters:	responseExpected – Type: bool
Returns:	err – Type: error

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

Internal Functions¶

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.

func (*EPaper296x128Bricklet) SetBootloaderMode(mode uint8) (status uint8, err error)¶

Parameters:	mode – Type: uint8, Range: See constants
Returns:	status – Type: uint8, Range: See constants err – Type: error

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:

e_paper_296x128_bricklet.BootloaderModeBootloader = 0
e_paper_296x128_bricklet.BootloaderModeFirmware = 1
e_paper_296x128_bricklet.BootloaderModeBootloaderWaitForReboot = 2
e_paper_296x128_bricklet.BootloaderModeFirmwareWaitForReboot = 3
e_paper_296x128_bricklet.BootloaderModeFirmwareWaitForEraseAndReboot = 4

For status:

e_paper_296x128_bricklet.BootloaderStatusOK = 0
e_paper_296x128_bricklet.BootloaderStatusInvalidMode = 1
e_paper_296x128_bricklet.BootloaderStatusNoChange = 2
e_paper_296x128_bricklet.BootloaderStatusEntryFunctionNotPresent = 3
e_paper_296x128_bricklet.BootloaderStatusDeviceIdentifierIncorrect = 4
e_paper_296x128_bricklet.BootloaderStatusCRCMismatch = 5

func (*EPaper296x128Bricklet) GetBootloaderMode() (mode uint8, err error)¶

Returns:	mode – Type: uint8, Range: See constants err – Type: error

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

For mode:

e_paper_296x128_bricklet.BootloaderModeBootloader = 0
e_paper_296x128_bricklet.BootloaderModeFirmware = 1
e_paper_296x128_bricklet.BootloaderModeBootloaderWaitForReboot = 2
e_paper_296x128_bricklet.BootloaderModeFirmwareWaitForReboot = 3
e_paper_296x128_bricklet.BootloaderModeFirmwareWaitForEraseAndReboot = 4

func (*EPaper296x128Bricklet) SetWriteFirmwarePointer(pointer uint32) (err error)¶

Parameters:	pointer – Type: uint32, Unit: 1 B, Range: [0 to 2³² - 1]
Returns:	err – Type: error

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.

func (*EPaper296x128Bricklet) WriteFirmware(data [64]uint8) (status uint8, err error)¶

Parameters:	data – Type: [64]uint8, Range: [0 to 255]
Returns:	status – Type: uint8, Range: [0 to 255] err – Type: error

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.

func (*EPaper296x128Bricklet) WriteUID(uid uint32) (err error)¶

Parameters:	uid – Type: uint32, Range: [0 to 2³² - 1]
Returns:	err – Type: error

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.

func (*EPaper296x128Bricklet) ReadUID() (uid uint32, err error)¶

Returns:	uid – Type: uint32, Range: [0 to 2³² - 1] err – Type: error

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

Constants¶

e_paper_296x128_bricklet.DeviceIdentifier¶

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

The GetIdentity() function and the (*IPConnection) RegisterEnumerateCallback callback of the IPConnection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

e_paper_296x128_bricklet.DeviceDisplayName¶: This constant represents the human readable name of a E-Paper 296x128 Bricklet.