Software / API Bindings / C/C++ for Microcontrollers / API Reference and Examples / Bricklets / E-Paper 296x128 Bricklet

C/C++ for Microcontrollers - E-Paper 296x128 Bricklet¶

This is the description of the C/C++ for Microcontrollers 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 C/C++ for Microcontrollers API bindings is part of their general description.

Examples¶

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

Hello World¶

Download (example_hello_world.c)

// This example is not self-contained.
// It requires usage of the example driver specific to your platform.
// See the HAL documentation.

#include "src/bindings/hal_common.h"
#include "src/bindings/bricklet_e_paper_296x128.h"

void check(int rc, const char *msg);
void example_setup(TF_HAL *hal);
void example_loop(TF_HAL *hal);

static TF_EPaper296x128 ep;

void example_setup(TF_HAL *hal) {
    // Create device object
    check(tf_e_paper_296x128_create(&ep, NULL, hal), "create device object");

    // Use black background
    check(tf_e_paper_296x128_fill_display(&ep,
                                          TF_E_PAPER_296X128_COLOR_BLACK), "call fill_display");

    // Write big white "Hello World" in the middle of the screen
    check(tf_e_paper_296x128_draw_text(&ep, 16, 48, TF_E_PAPER_296X128_FONT_24X32,
                                       TF_E_PAPER_296X128_COLOR_WHITE,
                                       TF_E_PAPER_296X128_ORIENTATION_HORIZONTAL,
                                       "Hello World"), "call draw_text");
    check(tf_e_paper_296x128_draw(&ep), "call draw");
}

void example_loop(TF_HAL *hal) {
    // Poll for callbacks
    tf_hal_callback_tick(hal, 0);
}

API¶

Most functions of the C/C++ bindings for microcontrollers return an error code (e_code).

Possible error codes are:

TF_E_OK = 0
TF_E_TIMEOUT = -1
TF_E_INVALID_PARAMETER = -2
TF_E_NOT_SUPPORTED = -3
TF_E_UNKNOWN_ERROR_CODE = -4
TF_E_STREAM_OUT_OF_SYNC = -5
TF_E_INVALID_CHAR_IN_UID = -6
TF_E_UID_TOO_LONG = -7
TF_E_UID_OVERFLOW = -8
TF_E_TOO_MANY_DEVICES = -9
TF_E_DEVICE_NOT_FOUND = -10
TF_E_WRONG_DEVICE_TYPE = -11
TF_E_LOCKED = -12
TF_E_PORT_NOT_FOUND = -13

(as defined in errors.h) as well as the errors returned from the hardware abstraction layer (HAL) that is used.

Use :cpp:func`tf_hal_strerror` (defined in the HAL's header file) to get an error string for an error code.

Data returned from the device, when a getter is called, is handled via output parameters. These parameters are labeled with the ret_ prefix. The bindings will not write to an output parameter if NULL or nullptr is passed. This can be used to ignore outputs that you are not interested in.

None of the functions listed below are thread-safe. See the API bindings description for details.

Basic Functions¶

int tf_e_paper_296x128_create(TF_EPaper296x128 *e_paper_296x128, const char *uid_or_port_name, TF_HAL *hal)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * uid – Type: const char * hal – Type: TF_HAL *
Returns:	e_code – Type: int

Creates the device object e_paper_296x128 with the optional unique device ID or port name uid_or_port_name and adds it to the HAL hal:

TF_EPaper296x128 e_paper_296x128;
tf_e_paper_296x128_create(&e_paper_296x128, NULL, &hal);

Normally uid_or_port_name can stay NULL. For more details about this see section UID or Port Name.

int tf_e_paper_296x128_destroy(TF_EPaper296x128 *e_paper_296x128)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Returns:	e_code – Type: int

Removes the device object e_paper_296x128 from its HAL and destroys it. The device object cannot be used anymore afterwards.

int tf_e_paper_296x128_draw(TF_EPaper296x128 *e_paper_296x128)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Returns:	e_code – Type: int

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 tf_e_paper_296x128_get_draw_status().

int tf_e_paper_296x128_get_draw_status(TF_EPaper296x128 *e_paper_296x128, uint8_t *ret_draw_status)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_draw_status – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 ret_draw_status:

TF_E_PAPER_296X128_DRAW_STATUS_IDLE = 0
TF_E_PAPER_296X128_DRAW_STATUS_COPYING = 1
TF_E_PAPER_296X128_DRAW_STATUS_DRAWING = 2

int tf_e_paper_296x128_write_black_white(TF_EPaper296x128 *e_paper_296x128, uint16_t x_start, uint8_t y_start, uint16_t x_end, uint8_t y_end, const bool *pixels, uint16_t pixels_length)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * x_start – Type: uint16_t, Range: [0 to 295] y_start – Type: uint8_t, Range: [0 to 127] x_end – Type: uint16_t, Range: [0 to 295] y_end – Type: uint8_t, Range: [0 to 127] pixels – Type: const bool * pixels_length – Type: uint16_t
Returns:	e_code – Type: int

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 tf_e_paper_296x128_draw().

Use tf_e_paper_296x128_write_color() to write red or gray pixels.

int tf_e_paper_296x128_read_black_white(TF_EPaper296x128 *e_paper_296x128, uint16_t x_start, uint8_t y_start, uint16_t x_end, uint8_t y_end, bool *ret_pixels, uint16_t *ret_pixels_length)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * x_start – Type: uint16_t, Range: [0 to 295] y_start – Type: uint8_t, Range: [0 to 127] x_end – Type: uint16_t, Range: [0 to 295] y_end – Type: uint8_t, Range: [0 to 127]
Output Parameters:	ret_pixels – Type: bool * ret_pixels_length – Type: uint16_t
Returns:	e_code – Type: int

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.

int tf_e_paper_296x128_write_color(TF_EPaper296x128 *e_paper_296x128, uint16_t x_start, uint8_t y_start, uint16_t x_end, uint8_t y_end, const bool *pixels, uint16_t pixels_length)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * x_start – Type: uint16_t, Range: [0 to 295] y_start – Type: uint8_t, Range: [0 to 127] x_end – Type: uint16_t, Range: [0 to 295] y_end – Type: uint8_t, Range: [0 to 127] pixels – Type: const bool * pixels_length – Type: uint16_t
Returns:	e_code – Type: int

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 tf_e_paper_296x128_write_black_white()). 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 tf_e_paper_296x128_draw().

Use tf_e_paper_296x128_write_black_white() to write black/white pixels.

int tf_e_paper_296x128_read_color(TF_EPaper296x128 *e_paper_296x128, uint16_t x_start, uint8_t y_start, uint16_t x_end, uint8_t y_end, bool *ret_pixels, uint16_t *ret_pixels_length)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * x_start – Type: uint16_t, Range: [0 to 295] y_start – Type: uint8_t, Range: [0 to 127] x_end – Type: uint16_t, Range: [0 to 295] y_end – Type: uint8_t, Range: [0 to 127]
Output Parameters:	ret_pixels – Type: bool * ret_pixels_length – Type: uint16_t
Returns:	e_code – Type: int

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.

int tf_e_paper_296x128_fill_display(TF_EPaper296x128 *e_paper_296x128, uint8_t color)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * color – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 tf_e_paper_296x128_draw().

The following constants are available for this function:

For color:

TF_E_PAPER_296X128_COLOR_BLACK = 0
TF_E_PAPER_296X128_COLOR_WHITE = 1
TF_E_PAPER_296X128_COLOR_RED = 2
TF_E_PAPER_296X128_COLOR_GRAY = 2

int tf_e_paper_296x128_draw_text(TF_EPaper296x128 *e_paper_296x128, uint16_t position_x, uint8_t position_y, uint8_t font, uint8_t color, uint8_t orientation, const char *text)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * position_x – Type: uint16_t, Range: [0 to 295] position_y – Type: uint8_t, Range: [0 to 127] font – Type: uint8_t, Range: See constants color – Type: uint8_t, Range: See constants orientation – Type: uint8_t, Range: See constants text – Type: const char[50]
Returns:	e_code – Type: int

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 tf_e_paper_296x128_draw().

The font conforms to code page 437.

The following constants are available for this function:

For font:

TF_E_PAPER_296X128_FONT_6X8 = 0
TF_E_PAPER_296X128_FONT_6X16 = 1
TF_E_PAPER_296X128_FONT_6X24 = 2
TF_E_PAPER_296X128_FONT_6X32 = 3
TF_E_PAPER_296X128_FONT_12X16 = 4
TF_E_PAPER_296X128_FONT_12X24 = 5
TF_E_PAPER_296X128_FONT_12X32 = 6
TF_E_PAPER_296X128_FONT_18X24 = 7
TF_E_PAPER_296X128_FONT_18X32 = 8
TF_E_PAPER_296X128_FONT_24X32 = 9

For color:

TF_E_PAPER_296X128_COLOR_BLACK = 0
TF_E_PAPER_296X128_COLOR_WHITE = 1
TF_E_PAPER_296X128_COLOR_RED = 2
TF_E_PAPER_296X128_COLOR_GRAY = 2

For orientation:

TF_E_PAPER_296X128_ORIENTATION_HORIZONTAL = 0
TF_E_PAPER_296X128_ORIENTATION_VERTICAL = 1

int tf_e_paper_296x128_draw_line(TF_EPaper296x128 *e_paper_296x128, uint16_t position_x_start, uint8_t position_y_start, uint16_t position_x_end, uint8_t position_y_end, uint8_t color)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * position_x_start – Type: uint16_t, Range: [0 to 295] position_y_start – Type: uint8_t, Range: [0 to 127] position_x_end – Type: uint16_t, Range: [0 to 295] position_y_end – Type: uint8_t, Range: [0 to 127] color – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 tf_e_paper_296x128_draw().

The following constants are available for this function:

For color:

TF_E_PAPER_296X128_COLOR_BLACK = 0
TF_E_PAPER_296X128_COLOR_WHITE = 1
TF_E_PAPER_296X128_COLOR_RED = 2
TF_E_PAPER_296X128_COLOR_GRAY = 2

int tf_e_paper_296x128_draw_box(TF_EPaper296x128 *e_paper_296x128, uint16_t position_x_start, uint8_t position_y_start, uint16_t position_x_end, uint8_t position_y_end, bool fill, uint8_t color)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * position_x_start – Type: uint16_t, Range: [0 to 295] position_y_start – Type: uint8_t, Range: [0 to 127] position_x_end – Type: uint16_t, Range: [0 to 295] position_y_end – Type: uint8_t, Range: [0 to 127] fill – Type: bool color – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 tf_e_paper_296x128_draw().

The following constants are available for this function:

For color:

TF_E_PAPER_296X128_COLOR_BLACK = 0
TF_E_PAPER_296X128_COLOR_WHITE = 1
TF_E_PAPER_296X128_COLOR_RED = 2
TF_E_PAPER_296X128_COLOR_GRAY = 2

Advanced Functions¶

int tf_e_paper_296x128_set_update_mode(TF_EPaper296x128 *e_paper_296x128, uint8_t update_mode)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * update_mode – Type: uint8_t, Range: See constants, Default: 0
Returns:	e_code – Type: int

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 update_mode:

TF_E_PAPER_296X128_UPDATE_MODE_DEFAULT = 0
TF_E_PAPER_296X128_UPDATE_MODE_BLACK_WHITE = 1
TF_E_PAPER_296X128_UPDATE_MODE_DELTA = 2

int tf_e_paper_296x128_get_update_mode(TF_EPaper296x128 *e_paper_296x128, uint8_t *ret_update_mode)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_update_mode – Type: uint8_t, Range: See constants, Default: 0
Returns:	e_code – Type: int

Returns the update mode as set by tf_e_paper_296x128_set_update_mode().

The following constants are available for this function:

For ret_update_mode:

TF_E_PAPER_296X128_UPDATE_MODE_DEFAULT = 0
TF_E_PAPER_296X128_UPDATE_MODE_BLACK_WHITE = 1
TF_E_PAPER_296X128_UPDATE_MODE_DELTA = 2

int tf_e_paper_296x128_set_display_type(TF_EPaper296x128 *e_paper_296x128, uint8_t display_type)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * display_type – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 display_type:

TF_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_RED = 0
TF_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_GRAY = 1

int tf_e_paper_296x128_get_display_type(TF_EPaper296x128 *e_paper_296x128, uint8_t *ret_display_type)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_display_type – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 ret_display_type:

TF_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_RED = 0
TF_E_PAPER_296X128_DISPLAY_TYPE_BLACK_WHITE_GRAY = 1

int tf_e_paper_296x128_set_display_driver(TF_EPaper296x128 *e_paper_296x128, uint8_t display_driver)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * display_driver – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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 display_driver:

TF_E_PAPER_296X128_DISPLAY_DRIVER_SSD1675A = 0
TF_E_PAPER_296X128_DISPLAY_DRIVER_SSD1680 = 1

New in version 2.0.3 (Plugin).

int tf_e_paper_296x128_get_display_driver(TF_EPaper296x128 *e_paper_296x128, uint8_t *ret_display_driver)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_display_driver – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

Returns the e-paper display driver.

The following constants are available for this function:

For ret_display_driver:

TF_E_PAPER_296X128_DISPLAY_DRIVER_SSD1675A = 0
TF_E_PAPER_296X128_DISPLAY_DRIVER_SSD1680 = 1

New in version 2.0.3 (Plugin).

int tf_e_paper_296x128_get_spitfp_error_count(TF_EPaper296x128 *e_paper_296x128, uint32_t *ret_error_count_ack_checksum, uint32_t *ret_error_count_message_checksum, uint32_t *ret_error_count_frame, uint32_t *ret_error_count_overflow)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_error_count_ack_checksum – Type: uint32_t, Range: [0 to 2³² - 1] ret_error_count_message_checksum – Type: uint32_t, Range: [0 to 2³² - 1] ret_error_count_frame – Type: uint32_t, Range: [0 to 2³² - 1] ret_error_count_overflow – Type: uint32_t, Range: [0 to 2³² - 1]
Returns:	e_code – Type: int

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.

int tf_e_paper_296x128_set_status_led_config(TF_EPaper296x128 *e_paper_296x128, uint8_t config)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * config – Type: uint8_t, Range: See constants, Default: 3
Returns:	e_code – Type: int

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:

TF_E_PAPER_296X128_STATUS_LED_CONFIG_OFF = 0
TF_E_PAPER_296X128_STATUS_LED_CONFIG_ON = 1
TF_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
TF_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_STATUS = 3

int tf_e_paper_296x128_get_status_led_config(TF_EPaper296x128 *e_paper_296x128, uint8_t *ret_config)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_config – Type: uint8_t, Range: See constants, Default: 3
Returns:	e_code – Type: int

Returns the configuration as set by tf_e_paper_296x128_set_status_led_config()

The following constants are available for this function:

For ret_config:

TF_E_PAPER_296X128_STATUS_LED_CONFIG_OFF = 0
TF_E_PAPER_296X128_STATUS_LED_CONFIG_ON = 1
TF_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
TF_E_PAPER_296X128_STATUS_LED_CONFIG_SHOW_STATUS = 3

int tf_e_paper_296x128_get_chip_temperature(TF_EPaper296x128 *e_paper_296x128, int16_t *ret_temperature)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_temperature – Type: int16_t, Unit: 1 °C, Range: [-2¹⁵ to 2¹⁵ - 1]
Returns:	e_code – Type: int

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.

int tf_e_paper_296x128_reset(TF_EPaper296x128 *e_paper_296x128)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Returns:	e_code – Type: int

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!

int tf_e_paper_296x128_get_identity(TF_EPaper296x128 *e_paper_296x128, char ret_uid[8], char ret_connected_uid[8], char *ret_position, uint8_t ret_hardware_version[3], uint8_t ret_firmware_version[3], uint16_t *ret_device_identifier)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_uid – Type: char[8] ret_connected_uid – Type: char[8] ret_position – Type: char, Range: ['a' to 'h', 'z'] ret_hardware_version – Type: uint8_t[3] 0: major – Type: uint8_t, Range: [0 to 255] 1: minor – Type: uint8_t, Range: [0 to 255] 2: revision – Type: uint8_t, Range: [0 to 255] ret_firmware_version – Type: uint8_t[3] 0: major – Type: uint8_t, Range: [0 to 255] 1: minor – Type: uint8_t, Range: [0 to 255] 2: revision – Type: uint8_t, Range: [0 to 255] ret_device_identifier – Type: uint16_t, Range: [0 to 2¹⁶ - 1]
Returns:	e_code – Type: int

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.

Callback Configuration Functions¶

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding tf_e_paper_296x128_register_*_callback function. The user_data passed to the registration function as well as the device that triggered the callback are passed to the registered callback handler.

Only one handler can be registered to a callback at the same time. To deregister a callback, call the tf_e_paper_296x128_register_*_callback function with NULL as handler.

Note

Using callbacks for recurring events is preferred compared to using getters. Polling for a callback requires writing one byte only. See here Optimizing Performance.

Warning

Calling bindings function from inside a callback handler is not allowed. See here Thread safety.

int tf_e_paper_296x128_register_draw_status_callback(TF_EPaper296x128 *e_paper_296x128, TF_EPaper296x128_DrawStatusHandler handler, void *user_data)¶

void handler(TF_EPaper296x128 *e_paper_296x128, uint8_t draw_status, void *user_data)

Callback Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * draw_status – Type: uint8_t, Range: See constants user_data – Type: void *

Callback for the current draw status. Will be called every time the draw status changes (see tf_e_paper_296x128_get_draw_status()).

The following constants are available for this function:

For draw_status:

TF_E_PAPER_296X128_DRAW_STATUS_IDLE = 0
TF_E_PAPER_296X128_DRAW_STATUS_COPYING = 1
TF_E_PAPER_296X128_DRAW_STATUS_DRAWING = 2

Virtual Functions¶

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object.

int tf_e_paper_296x128_get_response_expected(TF_EPaper296x128 *e_paper_296x128, uint8_t function_id, bool *ret_response_expected)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * function_id – Type: uint8_t, Range: See constants
Output Parameters:	ret_response_expected – Type: bool
Returns:	e_code – Type: int

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 tf_e_paper_296x128_set_response_expected(). 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 function_id:

TF_E_PAPER_296X128_FUNCTION_DRAW = 1
TF_E_PAPER_296X128_FUNCTION_WRITE_BLACK_WHITE = 3
TF_E_PAPER_296X128_FUNCTION_WRITE_COLOR = 5
TF_E_PAPER_296X128_FUNCTION_FILL_DISPLAY = 7
TF_E_PAPER_296X128_FUNCTION_DRAW_TEXT = 8
TF_E_PAPER_296X128_FUNCTION_DRAW_LINE = 9
TF_E_PAPER_296X128_FUNCTION_DRAW_BOX = 10
TF_E_PAPER_296X128_FUNCTION_SET_UPDATE_MODE = 12
TF_E_PAPER_296X128_FUNCTION_SET_DISPLAY_TYPE = 14
TF_E_PAPER_296X128_FUNCTION_SET_DISPLAY_DRIVER = 16
TF_E_PAPER_296X128_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
TF_E_PAPER_296X128_FUNCTION_SET_STATUS_LED_CONFIG = 239
TF_E_PAPER_296X128_FUNCTION_RESET = 243
TF_E_PAPER_296X128_FUNCTION_WRITE_UID = 248

int tf_e_paper_296x128_set_response_expected(TF_EPaper296x128 *e_paper_296x128, uint8_t function_id, bool response_expected)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * function_id – Type: uint8_t, Range: See constants response_expected – Type: bool
Returns:	e_code – Type: int

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 function_id:

TF_E_PAPER_296X128_FUNCTION_DRAW = 1
TF_E_PAPER_296X128_FUNCTION_WRITE_BLACK_WHITE = 3
TF_E_PAPER_296X128_FUNCTION_WRITE_COLOR = 5
TF_E_PAPER_296X128_FUNCTION_FILL_DISPLAY = 7
TF_E_PAPER_296X128_FUNCTION_DRAW_TEXT = 8
TF_E_PAPER_296X128_FUNCTION_DRAW_LINE = 9
TF_E_PAPER_296X128_FUNCTION_DRAW_BOX = 10
TF_E_PAPER_296X128_FUNCTION_SET_UPDATE_MODE = 12
TF_E_PAPER_296X128_FUNCTION_SET_DISPLAY_TYPE = 14
TF_E_PAPER_296X128_FUNCTION_SET_DISPLAY_DRIVER = 16
TF_E_PAPER_296X128_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
TF_E_PAPER_296X128_FUNCTION_SET_STATUS_LED_CONFIG = 239
TF_E_PAPER_296X128_FUNCTION_RESET = 243
TF_E_PAPER_296X128_FUNCTION_WRITE_UID = 248

int tf_e_paper_296x128_set_response_expected_all(TF_EPaper296x128 *e_paper_296x128, bool response_expected)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * response_expected – Type: bool
Returns:	e_code – Type: int

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.

int tf_e_paper_296x128_set_bootloader_mode(TF_EPaper296x128 *e_paper_296x128, uint8_t mode, uint8_t *ret_status)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * mode – Type: uint8_t, Range: See constants
Output Parameters:	ret_status – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

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:

TF_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER = 0
TF_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE = 1
TF_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
TF_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
TF_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For ret_status:

TF_E_PAPER_296X128_BOOTLOADER_STATUS_OK = 0
TF_E_PAPER_296X128_BOOTLOADER_STATUS_INVALID_MODE = 1
TF_E_PAPER_296X128_BOOTLOADER_STATUS_NO_CHANGE = 2
TF_E_PAPER_296X128_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
TF_E_PAPER_296X128_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
TF_E_PAPER_296X128_BOOTLOADER_STATUS_CRC_MISMATCH = 5

int tf_e_paper_296x128_get_bootloader_mode(TF_EPaper296x128 *e_paper_296x128, uint8_t *ret_mode)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_mode – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

Returns the current bootloader mode, see tf_e_paper_296x128_set_bootloader_mode().

The following constants are available for this function:

For ret_mode:

TF_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER = 0
TF_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE = 1
TF_E_PAPER_296X128_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
TF_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
TF_E_PAPER_296X128_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

int tf_e_paper_296x128_set_write_firmware_pointer(TF_EPaper296x128 *e_paper_296x128, uint32_t pointer)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * pointer – Type: uint32_t, Unit: 1 B, Range: [0 to 2³² - 1]
Returns:	e_code – Type: int

Sets the firmware pointer for tf_e_paper_296x128_write_firmware(). 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.

int tf_e_paper_296x128_write_firmware(TF_EPaper296x128 *e_paper_296x128, const uint8_t data[64], uint8_t *ret_status)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * data – Type: const uint8_t[64], Range: [0 to 255]
Output Parameters:	ret_status – Type: uint8_t, Range: [0 to 255]
Returns:	e_code – Type: int

Writes 64 Bytes of firmware at the position as written by tf_e_paper_296x128_set_write_firmware_pointer() 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.

int tf_e_paper_296x128_write_uid(TF_EPaper296x128 *e_paper_296x128, uint32_t uid)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 * uid – Type: uint32_t, Range: [0 to 2³² - 1]
Returns:	e_code – Type: int

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.

int tf_e_paper_296x128_read_uid(TF_EPaper296x128 *e_paper_296x128, uint32_t *ret_uid)¶

Parameters:	e_paper_296x128 – Type: TF_EPaper296x128 *
Output Parameters:	ret_uid – Type: uint32_t, Range: [0 to 2³² - 1]
Returns:	e_code – Type: int

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

Constants¶

TF_E_PAPER_296X128_DEVICE_IDENTIFIER¶

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

The functions tf_e_paper_296x128_get_identity() and tf_hal_get_device_info() have a device_identifier output parameter to specify the Brick's or Bricklet's type.

TF_E_PAPER_296X128_DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a E-Paper 296x128 Bricklet.