C/C++ - Real-Time Clock Bricklet 2.0

This is the description of the C/C++ API bindings for the Real-Time Clock Bricklet 2.0. General information and technical specifications for the Real-Time Clock Bricklet 2.0 are summarized in its hardware description.

An installation guide for the C/C++ API bindings is part of their general description.

Examples

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

Simple

Download (example_simple.c)

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#define __STDC_FORMAT_MACROS // for PRId64/PRIu64 in C++

#include <stdio.h>
#include <inttypes.h>

#include "ip_connection.h"
#include "bricklet_real_time_clock_v2.h"

#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Real-Time Clock Bricklet 2.0

int main(void) {
    // Create IP connection
    IPConnection ipcon;
    ipcon_create(&ipcon);

    // Create device object
    RealTimeClockV2 rtc;
    real_time_clock_v2_create(&rtc, UID, &ipcon);

    // Connect to brickd
    if(ipcon_connect(&ipcon, HOST, PORT) < 0) {
        fprintf(stderr, "Could not connect\n");
        return 1;
    }
    // Don't use device before ipcon is connected

    // Get current date and time
    uint16_t year; uint8_t month, day, hour, minute, second, centisecond, weekday;
    int64_t timestamp;
    if(real_time_clock_v2_get_date_time(&rtc, &year, &month, &day, &hour, &minute,
                                        &second, &centisecond, &weekday,
                                        &timestamp) < 0) {
        fprintf(stderr, "Could not get date and time, probably timeout\n");
        return 1;
    }

    printf("Year: %u\n", year);
    printf("Month: %u\n", month);
    printf("Day: %u\n", day);
    printf("Hour: %u\n", hour);
    printf("Minute: %u\n", minute);
    printf("Second: %u\n", second);
    printf("Centisecond: %u\n", centisecond);

    if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_MONDAY) {
        printf("Weekday: Monday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_TUESDAY) {
        printf("Weekday: Tuesday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_WEDNESDAY) {
        printf("Weekday: Wednesday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_THURSDAY) {
        printf("Weekday: Thursday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_FRIDAY) {
        printf("Weekday: Friday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_SATURDAY) {
        printf("Weekday: Saturday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_SUNDAY) {
        printf("Weekday: Sunday\n");
    }

    printf("Timestamp: %" PRId64 " ms\n", timestamp);

    printf("Press key to exit\n");
    getchar();
    real_time_clock_v2_destroy(&rtc);
    ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
    return 0;
}

Callback

Download (example_callback.c)

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#define __STDC_FORMAT_MACROS // for PRId64/PRIu64 in C++

#include <stdio.h>
#include <inttypes.h>

#include "ip_connection.h"
#include "bricklet_real_time_clock_v2.h"

#define HOST "localhost"
#define PORT 4223
#define UID "XYZ" // Change XYZ to the UID of your Real-Time Clock Bricklet 2.0

// Callback function for date and time callback
void cb_date_time(uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute,
                  uint8_t second, uint8_t centisecond, uint8_t weekday, int64_t timestamp,
                  void *user_data) {
    (void)user_data; // avoid unused parameter warning

    printf("Year: %u\n", year);
    printf("Month: %u\n", month);
    printf("Day: %u\n", day);
    printf("Hour: %u\n", hour);
    printf("Minute: %u\n", minute);
    printf("Second: %u\n", second);
    printf("Centisecond: %u\n", centisecond);

    if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_MONDAY) {
        printf("Weekday: Monday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_TUESDAY) {
        printf("Weekday: Tuesday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_WEDNESDAY) {
        printf("Weekday: Wednesday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_THURSDAY) {
        printf("Weekday: Thursday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_FRIDAY) {
        printf("Weekday: Friday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_SATURDAY) {
        printf("Weekday: Saturday\n");
    } else if(weekday == REAL_TIME_CLOCK_V2_WEEKDAY_SUNDAY) {
        printf("Weekday: Sunday\n");
    }

    printf("Timestamp: %" PRId64 "\n", timestamp);
    printf("\n");
}

int main(void) {
    // Create IP connection
    IPConnection ipcon;
    ipcon_create(&ipcon);

    // Create device object
    RealTimeClockV2 rtc;
    real_time_clock_v2_create(&rtc, UID, &ipcon);

    // Connect to brickd
    if(ipcon_connect(&ipcon, HOST, PORT) < 0) {
        fprintf(stderr, "Could not connect\n");
        return 1;
    }
    // Don't use device before ipcon is connected

    // Register date and time callback to function cb_date_time
    real_time_clock_v2_register_callback(&rtc,
                                         REAL_TIME_CLOCK_V2_CALLBACK_DATE_TIME,
                                         (void (*)(void))cb_date_time,
                                         NULL);

    // Set period for date and time callback to 5s (5000ms)
    real_time_clock_v2_set_date_time_callback_configuration(&rtc, 5000);

    printf("Press key to exit\n");
    getchar();
    real_time_clock_v2_destroy(&rtc);
    ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
    return 0;
}

API

Every function of the C/C++ bindings returns an integer which describes 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.

Possible error codes are:

  • E_OK = 0
  • E_TIMEOUT = -1
  • E_NO_STREAM_SOCKET = -2
  • E_HOSTNAME_INVALID = -3
  • E_NO_CONNECT = -4
  • E_NO_THREAD = -5
  • E_NOT_ADDED = -6 (unused since C/C++ bindings version 2.0.0)
  • E_ALREADY_CONNECTED = -7
  • E_NOT_CONNECTED = -8
  • E_INVALID_PARAMETER = -9
  • E_NOT_SUPPORTED = -10
  • E_UNKNOWN_ERROR_CODE = -11
  • E_STREAM_OUT_OF_SYNC = -12
  • E_INVALID_UID = -13
  • E_NON_ASCII_CHAR_IN_SECRET = -14

as defined in ip_connection.h.

All functions listed below are thread-safe.

Basic Functions

void real_time_clock_v2_create(RealTimeClockV2 *real_time_clock_v2, const char *uid, IPConnection *ipcon)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • uid – Type: const char *
  • ipcon – Type: IPConnection *

Creates the device object real_time_clock_v2 with the unique device ID uid and adds it to the IPConnection ipcon:

RealTimeClockV2 real_time_clock_v2;
real_time_clock_v2_create(&real_time_clock_v2, "YOUR_DEVICE_UID", &ipcon);

This device object can be used after the IP connection has been connected (see examples above).

void real_time_clock_v2_destroy(RealTimeClockV2 *real_time_clock_v2)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *

Removes the device object real_time_clock_v2 from its IPConnection and destroys it. The device object cannot be used anymore afterwards.

int real_time_clock_v2_set_date_time(RealTimeClockV2 *real_time_clock_v2, uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute, uint8_t second, uint8_t centisecond, uint8_t weekday)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • year – Type: uint16_t, Range: [2000 to 2099]
  • month – Type: uint8_t, Range: [1 to 12]
  • day – Type: uint8_t, Range: [1 to 31]
  • hour – Type: uint8_t, Range: [0 to 23]
  • minute – Type: uint8_t, Range: [0 to 59]
  • second – Type: uint8_t, Range: [0 to 59]
  • centisecond – Type: uint8_t, Range: [0 to 99]
  • weekday – Type: uint8_t, Range: See constants
Returns:
  • error_code – Type: int

Sets the current date (including weekday) and the current time.

If the backup battery is installed then the real-time clock keeps date and time even if the Bricklet is not powered by a Brick.

The real-time clock handles leap year and inserts the 29th of February accordingly. But leap seconds, time zones and daylight saving time are not handled.

The following constants are available for this function:

For weekday:

  • REAL_TIME_CLOCK_V2_WEEKDAY_MONDAY = 1
  • REAL_TIME_CLOCK_V2_WEEKDAY_TUESDAY = 2
  • REAL_TIME_CLOCK_V2_WEEKDAY_WEDNESDAY = 3
  • REAL_TIME_CLOCK_V2_WEEKDAY_THURSDAY = 4
  • REAL_TIME_CLOCK_V2_WEEKDAY_FRIDAY = 5
  • REAL_TIME_CLOCK_V2_WEEKDAY_SATURDAY = 6
  • REAL_TIME_CLOCK_V2_WEEKDAY_SUNDAY = 7
int real_time_clock_v2_get_date_time(RealTimeClockV2 *real_time_clock_v2, uint16_t *ret_year, uint8_t *ret_month, uint8_t *ret_day, uint8_t *ret_hour, uint8_t *ret_minute, uint8_t *ret_second, uint8_t *ret_centisecond, uint8_t *ret_weekday, int64_t *ret_timestamp)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_year – Type: uint16_t, Range: [2000 to 2099]
  • ret_month – Type: uint8_t, Range: [1 to 12]
  • ret_day – Type: uint8_t, Range: [1 to 31]
  • ret_hour – Type: uint8_t, Range: [0 to 23]
  • ret_minute – Type: uint8_t, Range: [0 to 59]
  • ret_second – Type: uint8_t, Range: [0 to 59]
  • ret_centisecond – Type: uint8_t, Range: [0 to 99]
  • ret_weekday – Type: uint8_t, Range: See constants
  • ret_timestamp – Type: int64_t, Unit: 1 ms, Range: [-263 to 263 - 1]
Returns:
  • error_code – Type: int

Returns the current date (including weekday) and the current time of the real-time.

The timestamp represents the current date and the the current time of the real-time clock converted to milliseconds and is an offset to 2000-01-01 00:00:00.0000.

The following constants are available for this function:

For ret_weekday:

  • REAL_TIME_CLOCK_V2_WEEKDAY_MONDAY = 1
  • REAL_TIME_CLOCK_V2_WEEKDAY_TUESDAY = 2
  • REAL_TIME_CLOCK_V2_WEEKDAY_WEDNESDAY = 3
  • REAL_TIME_CLOCK_V2_WEEKDAY_THURSDAY = 4
  • REAL_TIME_CLOCK_V2_WEEKDAY_FRIDAY = 5
  • REAL_TIME_CLOCK_V2_WEEKDAY_SATURDAY = 6
  • REAL_TIME_CLOCK_V2_WEEKDAY_SUNDAY = 7
int real_time_clock_v2_get_timestamp(RealTimeClockV2 *real_time_clock_v2, int64_t *ret_timestamp)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_timestamp – Type: int64_t, Unit: 1 ms, Range: [-263 to 263 - 1]
Returns:
  • error_code – Type: int

Returns the current date and the time of the real-time clock converted to milliseconds. The timestamp has an effective resolution of hundredths of a second and is an offset to 2000-01-01 00:00:00.0000.

Advanced Functions

int real_time_clock_v2_set_offset(RealTimeClockV2 *real_time_clock_v2, int8_t offset)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • offset – Type: int8_t, Unit: 217/100 ppm, Range: [-128 to 127]
Returns:
  • error_code – Type: int

Sets the offset the real-time clock should compensate for in 2.17 ppm steps between -277.76 ppm (-128) and +275.59 ppm (127).

The real-time clock time can deviate from the actual time due to the frequency deviation of its 32.768 kHz crystal. Even without compensation (factory default) the resulting time deviation should be at most ±20 ppm (±52.6 seconds per month).

This deviation can be calculated by comparing the same duration measured by the real-time clock (rtc_duration) an accurate reference clock (ref_duration).

For best results the configured offset should be set to 0 ppm first and then a duration of at least 6 hours should be measured.

The new offset (new_offset) can be calculated from the currently configured offset (current_offset) and the measured durations as follow:

new_offset = current_offset - round(1000000 * (rtc_duration - ref_duration) / rtc_duration / 2.17)

If you want to calculate the offset, then we recommend using the calibration dialog in Brick Viewer, instead of doing it manually.

The offset is saved in the EEPROM of the Bricklet and only needs to be configured once.

int real_time_clock_v2_get_offset(RealTimeClockV2 *real_time_clock_v2, int8_t *ret_offset)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_offset – Type: int8_t, Unit: 217/100 ppm, Range: [-128 to 127]
Returns:
  • error_code – Type: int

Returns the offset as set by real_time_clock_v2_set_offset().

int real_time_clock_v2_get_spitfp_error_count(RealTimeClockV2 *real_time_clock_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:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
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:
  • error_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 real_time_clock_v2_set_bootloader_mode(RealTimeClockV2 *real_time_clock_v2, uint8_t mode, uint8_t *ret_status)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • mode – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_status – Type: uint8_t, Range: See constants
Returns:
  • error_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:

  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_BOOTLOADER = 0
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_FIRMWARE = 1
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For ret_status:

  • REAL_TIME_CLOCK_V2_BOOTLOADER_STATUS_OK = 0
  • REAL_TIME_CLOCK_V2_BOOTLOADER_STATUS_INVALID_MODE = 1
  • REAL_TIME_CLOCK_V2_BOOTLOADER_STATUS_NO_CHANGE = 2
  • REAL_TIME_CLOCK_V2_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • REAL_TIME_CLOCK_V2_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • REAL_TIME_CLOCK_V2_BOOTLOADER_STATUS_CRC_MISMATCH = 5
int real_time_clock_v2_get_bootloader_mode(RealTimeClockV2 *real_time_clock_v2, uint8_t *ret_mode)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_mode – Type: uint8_t, Range: See constants
Returns:
  • error_code – Type: int

Returns the current bootloader mode, see real_time_clock_v2_set_bootloader_mode().

The following constants are available for this function:

For ret_mode:

  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_BOOTLOADER = 0
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_FIRMWARE = 1
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • REAL_TIME_CLOCK_V2_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
int real_time_clock_v2_set_write_firmware_pointer(RealTimeClockV2 *real_time_clock_v2, uint32_t pointer)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • pointer – Type: uint32_t, Unit: 1 B, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

Sets the firmware pointer for real_time_clock_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 real_time_clock_v2_write_firmware(RealTimeClockV2 *real_time_clock_v2, uint8_t data[64], uint8_t *ret_status)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • data – Type: uint8_t[64], Range: [0 to 255]
Output Parameters:
  • ret_status – Type: uint8_t, Range: [0 to 255]
Returns:
  • error_code – Type: int

Writes 64 Bytes of firmware at the position as written by real_time_clock_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 real_time_clock_v2_set_status_led_config(RealTimeClockV2 *real_time_clock_v2, uint8_t config)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • error_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:

  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_OFF = 0
  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_ON = 1
  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3
int real_time_clock_v2_get_status_led_config(RealTimeClockV2 *real_time_clock_v2, uint8_t *ret_config)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_config – Type: uint8_t, Range: See constants, Default: 3
Returns:
  • error_code – Type: int

Returns the configuration as set by real_time_clock_v2_set_status_led_config()

The following constants are available for this function:

For ret_config:

  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_OFF = 0
  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_ON = 1
  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • REAL_TIME_CLOCK_V2_STATUS_LED_CONFIG_SHOW_STATUS = 3
int real_time_clock_v2_get_chip_temperature(RealTimeClockV2 *real_time_clock_v2, int16_t *ret_temperature)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_temperature – Type: int16_t, Unit: 1 °C, Range: [-215 to 215 - 1]
Returns:
  • error_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 real_time_clock_v2_reset(RealTimeClockV2 *real_time_clock_v2)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Returns:
  • error_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 real_time_clock_v2_write_uid(RealTimeClockV2 *real_time_clock_v2, uint32_t uid)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • uid – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • error_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 real_time_clock_v2_read_uid(RealTimeClockV2 *real_time_clock_v2, uint32_t *ret_uid)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_uid – Type: uint32_t, Range: [0 to 232 - 1]
Returns:
  • error_code – Type: int

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

int real_time_clock_v2_get_identity(RealTimeClockV2 *real_time_clock_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:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_uid – Type: char[8]
  • ret_connected_uid – Type: char[8]
  • ret_position – Type: char, Range: ['a' to 'h', 'i', '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:
  • error_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). The Raspberry Pi HAT (Zero) Brick is always at position 'i' and the Bricklet connected to an Isolator Bricklet is always as 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

void real_time_clock_v2_register_callback(RealTimeClockV2 *real_time_clock_v2, int16_t callback_id, void (*function)(void), void *user_data)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • callback_id – Type: int16_t
  • function – Type: void (*)(void)
  • user_data – Type: void *

Registers the given function with the given callback_id. The user_data will be passed as the last parameter to the function.

The available callback IDs with corresponding function signatures are listed below.

int real_time_clock_v2_set_date_time_callback_configuration(RealTimeClockV2 *real_time_clock_v2, uint32_t period)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • error_code – Type: int

Sets the period with which the REAL_TIME_CLOCK_V2_CALLBACK_DATE_TIME callback is triggered periodically. A value of 0 turns the callback off.

int real_time_clock_v2_get_date_time_callback_configuration(RealTimeClockV2 *real_time_clock_v2, uint32_t *ret_period)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_period – Type: uint32_t, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Returns:
  • error_code – Type: int

Returns the period as set by real_time_clock_v2_set_date_time_callback_configuration().

int real_time_clock_v2_set_alarm(RealTimeClockV2 *real_time_clock_v2, int8_t month, int8_t day, int8_t hour, int8_t minute, int8_t second, int8_t weekday, int32_t interval)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • month – Type: int8_t, Range: [-1, 2000 to 2099] with constants
  • day – Type: int8_t, Range: [-1, 1 to 12] with constants
  • hour – Type: int8_t, Range: [-1, 1 to 31] with constants
  • minute – Type: int8_t, Range: [-1 to 23] with constants
  • second – Type: int8_t, Range: [-1 to 59] with constants
  • weekday – Type: int8_t, Range: [-1 to 59] with constants
  • interval – Type: int32_t, Unit: 1 s, Range: See constants
Returns:
  • error_code – Type: int

Configures a repeatable alarm. The REAL_TIME_CLOCK_V2_CALLBACK_ALARM callback is triggered if the current date and time matches the configured alarm.

Setting a parameter to -1 means that it should be disabled and doesn't take part in the match. Setting all parameters to -1 disables the alarm completely.

For example, to make the alarm trigger every day at 7:30 AM it can be configured as (-1, -1, 7, 30, -1, -1, -1). The hour is set to match 7 and the minute is set to match 30. The alarm is triggered if all enabled parameters match.

The interval has a special role. It allows to make the alarm reconfigure itself. This is useful if you need a repeated alarm that cannot be expressed by matching the current date and time. For example, to make the alarm trigger every 23 seconds it can be configured as (-1, -1, -1, -1, -1, -1, 23). Internally the Bricklet will take the current date and time, add 23 seconds to it and set the result as its alarm. The first alarm will be triggered 23 seconds after the call. Because the interval is not -1, the Bricklet will do the same again internally, take the current date and time, add 23 seconds to it and set that as its alarm. This results in a repeated alarm that triggers every 23 seconds.

The interval can also be used in combination with the other parameters. For example, configuring the alarm as (-1, -1, 7, 30, -1, -1, 300) results in an alarm that triggers every day at 7:30 AM and is then repeated every 5 minutes.

The following constants are available for this function:

For month:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For day:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For hour:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For minute:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For second:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For weekday:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For interval:

  • REAL_TIME_CLOCK_V2_ALARM_INTERVAL_DISABLED = -1
int real_time_clock_v2_get_alarm(RealTimeClockV2 *real_time_clock_v2, int8_t *ret_month, int8_t *ret_day, int8_t *ret_hour, int8_t *ret_minute, int8_t *ret_second, int8_t *ret_weekday, int32_t *ret_interval)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_month – Type: int8_t, Range: [-1, 2000 to 2099] with constants
  • ret_day – Type: int8_t, Range: [-1, 1 to 12] with constants
  • ret_hour – Type: int8_t, Range: [-1, 1 to 31] with constants
  • ret_minute – Type: int8_t, Range: [-1 to 23] with constants
  • ret_second – Type: int8_t, Range: [-1 to 59] with constants
  • ret_weekday – Type: int8_t, Range: [-1 to 59] with constants
  • ret_interval – Type: int32_t, Unit: 1 s, Range: See constants
Returns:
  • error_code – Type: int

Returns the alarm configuration as set by real_time_clock_v2_set_alarm().

The following constants are available for this function:

For ret_month:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For ret_day:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For ret_hour:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For ret_minute:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For ret_second:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For ret_weekday:

  • REAL_TIME_CLOCK_V2_ALARM_MATCH_DISABLED = -1

For ret_interval:

  • REAL_TIME_CLOCK_V2_ALARM_INTERVAL_DISABLED = -1

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the real_time_clock_v2_register_callback() function:

void my_callback(int value, void *user_data) {
    printf("Value: %d\n", value);
}

real_time_clock_v2_register_callback(&real_time_clock_v2,
                                     REAL_TIME_CLOCK_V2_CALLBACK_EXAMPLE,
                                     (void (*)(void))my_callback,
                                     NULL);

The available constants with corresponding function signatures are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

REAL_TIME_CLOCK_V2_CALLBACK_DATE_TIME
void callback(uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute, uint8_t second, uint8_t centisecond, uint8_t weekday, int64_t timestamp, void *user_data)
Callback Parameters:
  • year – Type: uint16_t, Range: [2000 to 2099]
  • month – Type: uint8_t, Range: [1 to 12]
  • day – Type: uint8_t, Range: [1 to 31]
  • hour – Type: uint8_t, Range: [0 to 23]
  • minute – Type: uint8_t, Range: [0 to 59]
  • second – Type: uint8_t, Range: [0 to 59]
  • centisecond – Type: uint8_t, Range: [0 to 99]
  • weekday – Type: uint8_t, Range: See constants
  • timestamp – Type: int64_t, Unit: 1 ms, Range: [-263 to 263 - 1]
  • user_data – Type: void *

This callback is triggered periodically with the period that is set by real_time_clock_v2_set_date_time_callback_configuration(). The parameters are the same as for real_time_clock_v2_get_date_time().

The following constants are available for this function:

For weekday:

  • REAL_TIME_CLOCK_V2_WEEKDAY_MONDAY = 1
  • REAL_TIME_CLOCK_V2_WEEKDAY_TUESDAY = 2
  • REAL_TIME_CLOCK_V2_WEEKDAY_WEDNESDAY = 3
  • REAL_TIME_CLOCK_V2_WEEKDAY_THURSDAY = 4
  • REAL_TIME_CLOCK_V2_WEEKDAY_FRIDAY = 5
  • REAL_TIME_CLOCK_V2_WEEKDAY_SATURDAY = 6
  • REAL_TIME_CLOCK_V2_WEEKDAY_SUNDAY = 7
REAL_TIME_CLOCK_V2_CALLBACK_ALARM
void callback(uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute, uint8_t second, uint8_t centisecond, uint8_t weekday, int64_t timestamp, void *user_data)
Callback Parameters:
  • year – Type: uint16_t, Range: [2000 to 2099]
  • month – Type: uint8_t, Range: [1 to 12]
  • day – Type: uint8_t, Range: [1 to 31]
  • hour – Type: uint8_t, Range: [0 to 23]
  • minute – Type: uint8_t, Range: [0 to 59]
  • second – Type: uint8_t, Range: [0 to 59]
  • centisecond – Type: uint8_t, Range: [0 to 99]
  • weekday – Type: uint8_t, Range: See constants
  • timestamp – Type: int64_t, Unit: 1 ms, Range: [-263 to 263 - 1]
  • user_data – Type: void *

This callback is triggered every time the current date and time matches the configured alarm (see real_time_clock_v2_set_alarm()). The parameters are the same as for real_time_clock_v2_get_date_time().

The following constants are available for this function:

For weekday:

  • REAL_TIME_CLOCK_V2_WEEKDAY_MONDAY = 1
  • REAL_TIME_CLOCK_V2_WEEKDAY_TUESDAY = 2
  • REAL_TIME_CLOCK_V2_WEEKDAY_WEDNESDAY = 3
  • REAL_TIME_CLOCK_V2_WEEKDAY_THURSDAY = 4
  • REAL_TIME_CLOCK_V2_WEEKDAY_FRIDAY = 5
  • REAL_TIME_CLOCK_V2_WEEKDAY_SATURDAY = 6
  • REAL_TIME_CLOCK_V2_WEEKDAY_SUNDAY = 7

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.

int real_time_clock_v2_get_api_version(RealTimeClockV2 *real_time_clock_v2, uint8_t ret_api_version[3])
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
Output Parameters:
  • ret_api_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]
Returns:
  • error_code – Type: int

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.

int real_time_clock_v2_get_response_expected(RealTimeClockV2 *real_time_clock_v2, uint8_t function_id, bool *ret_response_expected)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • function_id – Type: uint8_t, Range: See constants
Output Parameters:
  • ret_response_expected – Type: bool
Returns:
  • error_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 real_time_clock_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 send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

  • REAL_TIME_CLOCK_V2_FUNCTION_SET_DATE_TIME = 1
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_OFFSET = 4
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_DATE_TIME_CALLBACK_CONFIGURATION = 6
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_ALARM = 8
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • REAL_TIME_CLOCK_V2_FUNCTION_RESET = 243
  • REAL_TIME_CLOCK_V2_FUNCTION_WRITE_UID = 248
int real_time_clock_v2_set_response_expected(RealTimeClockV2 *real_time_clock_v2, uint8_t function_id, bool response_expected)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • function_id – Type: uint8_t, Range: See constants
  • response_expected – Type: bool
Returns:
  • error_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.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

  • REAL_TIME_CLOCK_V2_FUNCTION_SET_DATE_TIME = 1
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_OFFSET = 4
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_DATE_TIME_CALLBACK_CONFIGURATION = 6
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_ALARM = 8
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • REAL_TIME_CLOCK_V2_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • REAL_TIME_CLOCK_V2_FUNCTION_RESET = 243
  • REAL_TIME_CLOCK_V2_FUNCTION_WRITE_UID = 248
int real_time_clock_v2_set_response_expected_all(RealTimeClockV2 *real_time_clock_v2, bool response_expected)
Parameters:
  • real_time_clock_v2 – Type: RealTimeClockV2 *
  • response_expected – Type: bool
Returns:
  • error_code – Type: int

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

Constants

REAL_TIME_CLOCK_V2_DEVICE_IDENTIFIER

This constant is used to identify a Real-Time Clock Bricklet 2.0.

The real_time_clock_v2_get_identity() function and the IPCON_CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

REAL_TIME_CLOCK_V2_DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Real-Time Clock Bricklet 2.0.