Software / API Bindings / C/C++ for Microcontrollers / API Reference and Examples / Bricklets / OLED 128x64 Bricklet 2.0

C/C++ for Microcontrollers - OLED 128x64 Bricklet 2.0¶

This is the description of the C/C++ for Microcontrollers API bindings for the OLED 128x64 Bricklet 2.0. General information and technical specifications for the OLED 128x64 Bricklet 2.0 are summarized in its hardware description.

An installation guide for the 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_oled_128x64_v2.h"

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

static TF_OLED128x64V2 oled;

void example_setup(TF_HAL *hal) {
    // Create device object
    check(tf_oled_128x64_v2_create(&oled, NULL, hal), "create device object");

    // Clear display
    check(tf_oled_128x64_v2_clear_display(&oled), "call clear_display");

    // Write "Hello World" starting from upper left corner of the screen
    check(tf_oled_128x64_v2_write_line(&oled, 0, 0, "Hello World"), "call write_line");
}

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_oled_128x64_v2_create(TF_OLED128x64V2 *oled_128x64_v2, const char *uid_or_port_name, TF_HAL *hal)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * uid – Type: const char * hal – Type: TF_HAL *
Returns:	e_code – Type: int

Creates the device object oled_128x64_v2 with the optional unique device ID or port name uid_or_port_name and adds it to the HAL hal:

TF_OLED128x64V2 oled_128x64_v2;
tf_oled_128x64_v2_create(&oled_128x64_v2, NULL, &hal);

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

int tf_oled_128x64_v2_destroy(TF_OLED128x64V2 *oled_128x64_v2)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
Returns:	e_code – Type: int

Removes the device object oled_128x64_v2 from its HAL and destroys it. The device object cannot be used anymore afterwards.

int tf_oled_128x64_v2_write_pixels(TF_OLED128x64V2 *oled_128x64_v2, uint8_t x_start, uint8_t y_start, uint8_t x_end, uint8_t y_end, const bool *pixels, uint16_t pixels_length)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * x_start – Type: uint8_t, Range: [0 to 127] y_start – Type: uint8_t, Range: [0 to 63] x_end – Type: uint8_t, Range: [0 to 127] y_end – Type: uint8_t, Range: [0 to 63] pixels – Type: const bool * pixels_length – Type: uint16_t
Returns:	e_code – Type: int

Writes pixels to 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.

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

If automatic draw is disabled the pixels are written to an internal buffer and the buffer is transferred to the display only after tf_oled_128x64_v2_draw_buffered_frame() is called. This can be used to avoid flicker when drawing a complex frame in multiple steps.

Automatic draw can be configured with the tf_oled_128x64_v2_set_display_configuration() function.

int tf_oled_128x64_v2_read_pixels(TF_OLED128x64V2 *oled_128x64_v2, uint8_t x_start, uint8_t y_start, uint8_t x_end, uint8_t y_end, bool *ret_pixels, uint16_t *ret_pixels_length)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * x_start – Type: uint8_t, Range: [0 to 127] y_start – Type: uint8_t, Range: [0 to 63] x_end – Type: uint8_t, Range: [0 to 127] y_end – Type: uint8_t, Range: [0 to 63]
Output Parameters:	ret_pixels – Type: bool * ret_pixels_length – Type: uint16_t
Returns:	e_code – Type: int

Reads pixels from the specified window.

The pixels are read from the window line by line top to bottom and each line is read from left to right.

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

If automatic draw is disabled the pixels are read from the internal buffer (see tf_oled_128x64_v2_draw_buffered_frame()).

Automatic draw can be configured with the tf_oled_128x64_v2_set_display_configuration() function.

int tf_oled_128x64_v2_clear_display(TF_OLED128x64V2 *oled_128x64_v2)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
Returns:	e_code – Type: int

Clears the complete content of the display.

If automatic draw is enabled (default) the pixels are directly cleared.

If automatic draw is disabled the the internal buffer is cleared and the buffer is transferred to the display only after tf_oled_128x64_v2_draw_buffered_frame() is called. This can be used to avoid flicker when drawing a complex frame in multiple steps.

Automatic draw can be configured with the tf_oled_128x64_v2_set_display_configuration() function.

int tf_oled_128x64_v2_write_line(TF_OLED128x64V2 *oled_128x64_v2, uint8_t line, uint8_t position, const char *text)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * line – Type: uint8_t, Range: [0 to 7] position – Type: uint8_t, Range: [0 to 21] text – Type: const char[22]
Returns:	e_code – Type: int

Writes text to a specific line with a specific position. The text can have a maximum of 22 characters.

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

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

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

If automatic draw is disabled the text is written to an internal buffer and the buffer is transferred to the display only after tf_oled_128x64_v2_draw_buffered_frame() is called. This can be used to avoid flicker when drawing a complex frame in multiple steps.

Automatic draw can be configured with the tf_oled_128x64_v2_set_display_configuration() function.

The font conforms to code page 437.

int tf_oled_128x64_v2_draw_buffered_frame(TF_OLED128x64V2 *oled_128x64_v2, bool force_complete_redraw)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * force_complete_redraw – Type: bool
Returns:	e_code – Type: int

Draws the currently buffered frame. Normally each call of tf_oled_128x64_v2_write_pixels() and tf_oled_128x64_v2_write_line() draws directly onto the display. If you turn automatic draw off (tf_oled_128x64_v2_set_display_configuration()), the data is written in an internal buffer and only transferred to the display by calling this function. This can be used to avoid flicker when drawing a complex frame in multiple steps.

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

Advanced Functions¶

int tf_oled_128x64_v2_set_display_configuration(TF_OLED128x64V2 *oled_128x64_v2, uint8_t contrast, bool invert, bool automatic_draw)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * contrast – Type: uint8_t, Range: [0 to 255], Default: 143 invert – Type: bool, Default: false automatic_draw – Type: bool, Default: true
Returns:	e_code – Type: int

Sets the configuration of the display.

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

If automatic draw is set to true, the display is automatically updated with every call of tf_oled_128x64_v2_write_pixels() or tf_oled_128x64_v2_write_line(). If it is set to false, the changes are written into an internal buffer and only shown on the display after a call of tf_oled_128x64_v2_draw_buffered_frame().

int tf_oled_128x64_v2_get_display_configuration(TF_OLED128x64V2 *oled_128x64_v2, uint8_t *ret_contrast, bool *ret_invert, bool *ret_automatic_draw)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
Output Parameters:	ret_contrast – Type: uint8_t, Range: [0 to 255], Default: 143 ret_invert – Type: bool, Default: false ret_automatic_draw – Type: bool, Default: true
Returns:	e_code – Type: int

Returns the configuration as set by tf_oled_128x64_v2_set_display_configuration().

int tf_oled_128x64_v2_get_spitfp_error_count(TF_OLED128x64V2 *oled_128x64_v2, 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:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
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_oled_128x64_v2_set_status_led_config(TF_OLED128x64V2 *oled_128x64_v2, uint8_t config)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_OLED_128X64_V2_STATUS_LED_CONFIG_OFF = 0
TF_OLED_128X64_V2_STATUS_LED_CONFIG_ON = 1
TF_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
TF_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3

int tf_oled_128x64_v2_get_status_led_config(TF_OLED128x64V2 *oled_128x64_v2, uint8_t *ret_config)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
Output Parameters:	ret_config – Type: uint8_t, Range: See constants, Default: 3
Returns:	e_code – Type: int

Returns the configuration as set by tf_oled_128x64_v2_set_status_led_config()

The following constants are available for this function:

For ret_config:

TF_OLED_128X64_V2_STATUS_LED_CONFIG_OFF = 0
TF_OLED_128X64_V2_STATUS_LED_CONFIG_ON = 1
TF_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
TF_OLED_128X64_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3

int tf_oled_128x64_v2_get_chip_temperature(TF_OLED128x64V2 *oled_128x64_v2, int16_t *ret_temperature)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
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_oled_128x64_v2_reset(TF_OLED128x64V2 *oled_128x64_v2)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
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_oled_128x64_v2_get_identity(TF_OLED128x64V2 *oled_128x64_v2, 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:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
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.

Virtual Functions¶

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

int tf_oled_128x64_v2_get_response_expected(TF_OLED128x64V2 *oled_128x64_v2, uint8_t function_id, bool *ret_response_expected)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_oled_128x64_v2_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_OLED_128X64_V2_FUNCTION_WRITE_PIXELS = 1
TF_OLED_128X64_V2_FUNCTION_CLEAR_DISPLAY = 3
TF_OLED_128X64_V2_FUNCTION_SET_DISPLAY_CONFIGURATION = 4
TF_OLED_128X64_V2_FUNCTION_WRITE_LINE = 6
TF_OLED_128X64_V2_FUNCTION_DRAW_BUFFERED_FRAME = 7
TF_OLED_128X64_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
TF_OLED_128X64_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
TF_OLED_128X64_V2_FUNCTION_RESET = 243
TF_OLED_128X64_V2_FUNCTION_WRITE_UID = 248

int tf_oled_128x64_v2_set_response_expected(TF_OLED128x64V2 *oled_128x64_v2, uint8_t function_id, bool response_expected)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_OLED_128X64_V2_FUNCTION_WRITE_PIXELS = 1
TF_OLED_128X64_V2_FUNCTION_CLEAR_DISPLAY = 3
TF_OLED_128X64_V2_FUNCTION_SET_DISPLAY_CONFIGURATION = 4
TF_OLED_128X64_V2_FUNCTION_WRITE_LINE = 6
TF_OLED_128X64_V2_FUNCTION_DRAW_BUFFERED_FRAME = 7
TF_OLED_128X64_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
TF_OLED_128X64_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
TF_OLED_128X64_V2_FUNCTION_RESET = 243
TF_OLED_128X64_V2_FUNCTION_WRITE_UID = 248

int tf_oled_128x64_v2_set_response_expected_all(TF_OLED128x64V2 *oled_128x64_v2, bool response_expected)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_oled_128x64_v2_set_bootloader_mode(TF_OLED128x64V2 *oled_128x64_v2, uint8_t mode, uint8_t *ret_status)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER = 0
TF_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE = 1
TF_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
TF_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
TF_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For ret_status:

TF_OLED_128X64_V2_BOOTLOADER_STATUS_OK = 0
TF_OLED_128X64_V2_BOOTLOADER_STATUS_INVALID_MODE = 1
TF_OLED_128X64_V2_BOOTLOADER_STATUS_NO_CHANGE = 2
TF_OLED_128X64_V2_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
TF_OLED_128X64_V2_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
TF_OLED_128X64_V2_BOOTLOADER_STATUS_CRC_MISMATCH = 5

int tf_oled_128x64_v2_get_bootloader_mode(TF_OLED128x64V2 *oled_128x64_v2, uint8_t *ret_mode)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
Output Parameters:	ret_mode – Type: uint8_t, Range: See constants
Returns:	e_code – Type: int

Returns the current bootloader mode, see tf_oled_128x64_v2_set_bootloader_mode().

The following constants are available for this function:

For ret_mode:

TF_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER = 0
TF_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE = 1
TF_OLED_128X64_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
TF_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
TF_OLED_128X64_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

int tf_oled_128x64_v2_set_write_firmware_pointer(TF_OLED128x64V2 *oled_128x64_v2, uint32_t pointer)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * pointer – Type: uint32_t, Unit: 1 B, Range: [0 to 2³² - 1]
Returns:	e_code – Type: int

Sets the firmware pointer for tf_oled_128x64_v2_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_oled_128x64_v2_write_firmware(TF_OLED128x64V2 *oled_128x64_v2, const uint8_t data[64], uint8_t *ret_status)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_oled_128x64_v2_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_oled_128x64_v2_write_uid(TF_OLED128x64V2 *oled_128x64_v2, uint32_t uid)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 * 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_oled_128x64_v2_read_uid(TF_OLED128x64V2 *oled_128x64_v2, uint32_t *ret_uid)¶

Parameters:	oled_128x64_v2 – Type: TF_OLED128x64V2 *
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_OLED_128X64_V2_DEVICE_IDENTIFIER¶

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

The functions tf_oled_128x64_v2_get_identity() and tf_hal_get_device_info() have a device_identifier output parameter to specify the Brick's or Bricklet's type.

TF_OLED_128X64_V2_DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a OLED 128x64 Bricklet 2.0.