#!/usr/bin/env python3 # -*- coding: UTF-8 -*- """ I2C RTC driver for DS1307 https://github.com/mcauser/micropython-tinyrtc-i2c MIT License Copyright (c) 2018 Mike Causer Extended 2023 by brainelectronics Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. BCD Format: https://en.wikipedia.org/wiki/Binary-coded_decimal """ # system packages from machine import I2C try: from micropython import const except ImportError: def const(x): return x class _Subscriptable(): def __getitem__(self, item): return None _subscriptable = _Subscriptable() Optional = _subscriptable Tuple = _subscriptable DATETIME_REG = const(0) # 0x00-0x06 CHIP_HALT = const(128) CONTROL_REG = const(7) # 0x07 RAM_REG = const(8) # 0x08-0x3F class DS1307(object): """Driver for the DS1307 RTC.""" def __init__(self, addr=0x68, i2c: Optional[I2C] = None) -> None: """ Constructs a new instance :param addr: The I2C bus address of the EEPROM :type addr: int :param i2c: I2C object :type i2c: I2C """ self._addr = addr if i2c is None: # default assignment, check the docs self._i2c = I2C(0) else: self._i2c = i2c self._weekday_start = 0 self._halt = False @property def addr(self) -> int: """ Get the DS1307 I2C bus address :returns: DS1307 I2C bus address :rtype: int """ return self._addr @property def weekday_start(self) -> int: """ Get the start of the weekday :returns: Weekday start :rtype: int """ return self._weekday_start @weekday_start.setter def weekday_start(self, value: int) -> None: """Set the start of the weekday""" if 0 <= value <= 6: self._weekday_start = value else: raise ValueError("Weekday can only be in range 0-6") @property def datetime(self) -> Tuple[int, int, int, int, int, int, int, int]: """ Get the current datetime (2023, 4, 18, 0, 10, 34, 4, 108) y, m, d, h, m, s, wd, yd :returns: (year, month, day, hour, minute, second, weekday, yearday) :rtype: Tuple[int, int, int, int, int, int, int, int] """ buf = bytearray(7) buf = self._i2c.readfrom_mem(self._addr, DATETIME_REG, 7) year = self._bcd_to_dec(buf[6]) + 2000 month = self._bcd_to_dec(buf[5]) day = self._bcd_to_dec(buf[4]) yearday = self.day_of_year(year=year, month=month, day=day) return ( year, month, day, self._bcd_to_dec(buf[2]), # hour self._bcd_to_dec(buf[1]), # minute self._bcd_to_dec(buf[0] & 0x7F), # second self._bcd_to_dec(buf[3] - self._weekday_start), # weekday yearday, ) @datetime.setter def datetime(self, datetime: Tuple[int, int, int, int, int, int, int, int]) -> None: # noqa: E501 """ Set datetime (2023, 4, 18, 20, 23, 38, 1, 108) by time.gmtime(time.time()) y, m, d, h, min,sec,wday, yday 0, 1, 2, 3, 4, 5, 6, 7 :param datetime: The datetime :type datetime: Tuple[int, int, int, int, int, int, int, int] """ buf = bytearray(7) # msb = CH, 1 = halt, 0 = go buf[0] = self._dec_to_bcd(datetime[5]) & 0x7F # second buf[1] = self._dec_to_bcd(datetime[4]) # minute buf[2] = self._dec_to_bcd(datetime[3]) # hour buf[3] = self._dec_to_bcd(datetime[6] + self._weekday_start) buf[4] = self._dec_to_bcd(datetime[2]) # day buf[5] = self._dec_to_bcd(datetime[1]) # month buf[6] = self._dec_to_bcd(datetime[0] - 2000) # year if (self._halt): buf[0] |= (1 << 7) self._i2c.writeto_mem(self._addr, DATETIME_REG, buf) @property def year(self) -> int: """ Get the year from the RTC :returns: Year of RTC :rtype: int """ return self.datetime[0] @property def month(self) -> int: """ Get the month from the RTC :returns: Month of RTC :rtype: int """ return self.datetime[1] @property def day(self) -> int: """ Get the day from the RTC :returns: Day of RTC :rtype: int """ return self.datetime[2] @property def hour(self) -> int: """ Get the hour from the RTC :returns: Hour of RTC :rtype: int """ return self.datetime[3] @property def minute(self) -> int: """ Get the minute from the RTC :returns: Minute of RTC :rtype: int """ return self.datetime[4] @property def second(self) -> int: """ Get the second from the RTC :returns: Second of RTC :rtype: int """ return self.datetime[5] @property def weekday(self) -> int: """ Get the weekday from the RTC :returns: Weekday of RTC :rtype: int """ return self.datetime[5] @property def yearday(self) -> int: """ Get the yearday from the RTC :returns: Yearday of RTC :rtype: int """ return self.datetime[7] def is_leap_year(self, year: int) -> bool: """ Determines whether the specified year is a leap year. :param year: The year :type year: int :returns: True if the specified year is leap year, False otherwise. :rtype: bool """ return (year % 4 == 0) def day_of_year(self, year: int, month: int, day: int) -> int: """ Get the day of the year :param year: The year :type year: int :param month: The month :type month: int :param day: The day :type day: int :returns: Day of the year, January 1 is day 1 :rtype: int """ month_days = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] year -= 2000 days16 = day for x in range(1, month): days16 += month_days[x - 1] if month >= 2 and self.is_leap_year(year=year): days16 += 1 return days16 @property def halt(self) -> bool: """ Get status of DS1307 :returns: Status of DS1307 :rtype: bool """ return self._halt @halt.setter def halt(self, value: bool = False) -> None: """ Power up or power down the RTC oscillator :param value: The value :type value: bool """ reg = self._i2c.readfrom_mem(self._addr, DATETIME_REG, 1)[0] if value: reg |= CHIP_HALT else: reg &= ~CHIP_HALT self._halt = bool(value) self._i2c.writeto_mem(self._addr, DATETIME_REG, bytearray([reg])) def square_wave(self, sqw: int = 0, out: int = 0) -> None: """ Output square wave on pin SQ at 1Hz, 4.096kHz, 8.192kHz or 32.768kHz, or disable the oscillator and output logic level high/low. """ if sqw not in (0, 1, 4, 8, 32): raise ValueError( "Squarewave can be set to 0Hz, 1Hz, {}Hz, {}Hz or {}Hz".format( 2 ** 12, 2 ** 13, 2 ** 15) ) rs0 = 1 if sqw == 4 or sqw == 32 else 0 rs1 = 1 if sqw == 8 or sqw == 32 else 0 out = 1 if out > 0 else 0 sqw = 1 if sqw > 0 else 0 reg = rs0 | rs1 << 1 | sqw << 4 | out << 7 self._i2c.writeto_mem(self._addr, CONTROL_REG, bytearray([reg])) def _dec_to_bcd(self, value: int) -> int: """ Convert decimal to binary coded decimal (BCD) format :param value: The value :type value: int :returns: Binary coded decimal (BCD) format :rtype: int """ return (value // 10) << 4 | (value % 10) def _bcd_to_dec(self, value: int) -> int: """ Convert binary coded decimal (BCD) format to decimal :param value: The value :type value: int :returns: Decimal value :rtype: int """ return ((value >> 4) * 10) + (value & 0x0F)