class Tinkerforge::BrickletRealTimeClock

Battery-backed real-time clock

Constants

CALLBACK_ALARM

This callback is triggered every time the current date and time matches the configured alarm (see BrickletRealTimeClock#set_alarm). The parameters are the same as for BrickletRealTimeClock#get_date_time and BrickletRealTimeClock#get_timestamp combined.

.. versionadded

2.0.1$nbsp;(Plugin)

CALLBACK_DATE_TIME

This callback is triggered periodically with the period that is set by BrickletRealTimeClock#set_date_time_callback_period. The parameters are the same as for BrickletRealTimeClock#get_date_time and BrickletRealTimeClock#get_timestamp combined.

The CALLBACK_DATE_TIME callback is only triggered if the date or time changed since the last triggering.

.. versionadded

2.0.1$nbsp;(Plugin)

Public Class Methods

new(uid, ipcon) click to toggle source

Creates an object with the unique device ID uid and adds it to the IP Connection ipcon.

Calls superclass method
# File lib/tinkerforge/bricklet_real_time_clock.rb, line 59
def initialize(uid, ipcon)
  super uid, ipcon, DEVICE_IDENTIFIER, DEVICE_DISPLAY_NAME

  @api_version = [2, 0, 1]

  @response_expected[FUNCTION_SET_DATE_TIME] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_DATE_TIME] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_TIMESTAMP] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_OFFSET] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_OFFSET] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_DATE_TIME_CALLBACK_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_DATE_TIME_CALLBACK_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_ALARM] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_ALARM] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IDENTITY] = RESPONSE_EXPECTED_ALWAYS_TRUE

  @callback_formats[CALLBACK_DATE_TIME] = [25, 'S C C C C C C C q']
  @callback_formats[CALLBACK_ALARM] = [25, 'S C C C C C C C q']

  @ipcon.add_device self
end

Public Instance Methods

get_alarm() click to toggle source

Returns the alarm configuration as set by BrickletRealTimeClock#set_alarm.

.. versionadded

2.0.1$nbsp;(Plugin)

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 207
def get_alarm
  check_validity

  send_request FUNCTION_GET_ALARM, [], '', 18, 'c c c c c c l'
end
get_date_time() click to toggle source

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

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 97
def get_date_time
  check_validity

  send_request FUNCTION_GET_DATE_TIME, [], '', 17, 'S C C C C C C C'
end
get_date_time_callback_period() click to toggle source

Returns the period as set by BrickletRealTimeClock#set_date_time_callback_period.

.. versionadded

2.0.1$nbsp;(Plugin)

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 166
def get_date_time_callback_period
  check_validity

  send_request FUNCTION_GET_DATE_TIME_CALLBACK_PERIOD, [], '', 12, 'L'
end
get_identity() click to toggle source

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 :ref:`Isolator Bricklet <isolator_bricklet>` is always at position 'z'.

The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 223
def get_identity
  send_request FUNCTION_GET_IDENTITY, [], '', 33, 'Z8 Z8 k C3 C3 S'
end
get_offset() click to toggle source

Returns the offset as set by BrickletRealTimeClock#set_offset.

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 144
def get_offset
  check_validity

  send_request FUNCTION_GET_OFFSET, [], '', 9, 'c'
end
get_timestamp() click to toggle source

Returns the current date and the time of the real-time clock. The timestamp has an effective resolution of hundredths of a second and is an offset to 2000-01-01 00:00:00.000.

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 106
def get_timestamp
  check_validity

  send_request FUNCTION_GET_TIMESTAMP, [], '', 16, 'q'
end
register_callback(id, &block) click to toggle source

Registers a callback with ID id to the block block.

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 228
def register_callback(id, &block)
  callback = block
  @registered_callbacks[id] = callback
end
set_alarm(month, day, hour, minute, second, weekday, interval) click to toggle source

Configures a repeatable alarm. The 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.

.. versionadded

2.0.1$nbsp;(Plugin)

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 198
def set_alarm(month, day, hour, minute, second, weekday, interval)
  check_validity

  send_request FUNCTION_SET_ALARM, [month, day, hour, minute, second, weekday, interval], 'c c c c c c l', 8, ''
end
set_date_time(year, month, day, hour, minute, second, centisecond, weekday) click to toggle source

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.

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 89
def set_date_time(year, month, day, hour, minute, second, centisecond, weekday)
  check_validity

  send_request FUNCTION_SET_DATE_TIME, [year, month, day, hour, minute, second, centisecond, weekday], 'S C C C C C C C', 8, ''
end
set_date_time_callback_period(period) click to toggle source

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

The CALLBACK_DATE_TIME Callback is only triggered if the date or time changed since the last triggering.

.. versionadded

2.0.1$nbsp;(Plugin)

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 157
def set_date_time_callback_period(period)
  check_validity

  send_request FUNCTION_SET_DATE_TIME_CALLBACK_PERIOD, [period], 'L', 8, ''
end
set_offset(offset) click to toggle source

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.

# File lib/tinkerforge/bricklet_real_time_clock.rb, line 137
def set_offset(offset)
  check_validity

  send_request FUNCTION_SET_OFFSET, [offset], 'c', 8, ''
end