DS1307.py

'''
    DS1307 RTC drive

    Author: shaoziyang
    Date:   2018.3

    http://www.micropython.org.cn
'''
from machine import I2C, Pin

DS1307_I2C_ADDRESS  = (104)
DS1307_REG_SECOND   = (0)
DS1307_REG_MINUTE   = (1)
DS1307_REG_HOUR     = (2)
DS1307_REG_WEEKDAY  = (3)
DS1307_REG_DAY      = (4)
DS1307_REG_MONTH    = (5)
DS1307_REG_YEAR     = (6)
DS1307_REG_CTRL     = (7)
DS1307_REG_RAM      = (8)

class DS1307():
    def __init__(self, i2c):
        self.i2c = i2c

    # set reg
    def	setReg(self, reg, dat):
        buf	= bytearray(2)
        buf[0] = reg
        buf[1] = dat
        self.i2c.writeto(DS1307_I2C_ADDRESS, buf)

    # get reg
    def	getReg(self, reg):
        buf	= bytearray(1)
        buf[0] = reg
        self.i2c.writeto(DS1307_I2C_ADDRESS, buf)
        t =	self.i2c.readfrom(DS1307_I2C_ADDRESS, 1)
        return t[0]

    def start(self):
        t = self.getReg(DS1307_REG_SECOND)
        self.setReg(DS1307_REG_SECOND, t&0x7F)

    def stop(self):
        t = self.getReg(DS1307_REG_SECOND)
        self.setReg(DS1307_REG_SECOND, t|0x80)

    def DecToHex(self, dat):
        return (dat//10) * 16 + (dat%10)

    def HexToDec(self, dat):
        return (dat//16) * 10 + (dat%16)

    def DateTime(self, DT=None):
        if DT == None:
            self.i2c.writeto(DS1307_I2C_ADDRESS, bytearray([0]))
            buf = self.i2c.readfrom(DS1307_I2C_ADDRESS, 7)
            DT = [0] * 8
            DT[0] = self.HexToDec(buf[6]) + 2000
            DT[1] = self.HexToDec(buf[5])
            DT[2] = self.HexToDec(buf[4])
            DT[3] = self.HexToDec(buf[3])
            DT[4] = self.HexToDec(buf[2])
            DT[5] = self.HexToDec(buf[1])
            DT[6] = self.HexToDec(buf[0])
            DT[7] = 0
            return DT
        else:
            buf = bytearray(8)
            buf[0] = 0
            buf[1] = self.DecToHex(DT[6]%60)    # second
            buf[2] = self.DecToHex(DT[5]%60)    # minute
            buf[3] = self.DecToHex(DT[4]%24)    # hour
            buf[4] = self.DecToHex(DT[3]%8)     # week day
            buf[5] = self.DecToHex(DT[2]%32)    # date
            buf[6] = self.DecToHex(DT[1]%13)    # month
            buf[7] = self.DecToHex(DT[0]%100)   # year
            self.i2c.writeto(DS1307_I2C_ADDRESS, buf) 

    def Year(self, year = None):
        if year == None:
            return self.HexToDec(self.getReg(DS1307_REG_YEAR)) + 2000
        else:
            self.setReg(DS1307_REG_YEAR, self.DecToHex(year%100))

    def Month(self, month = None):
        if month == None:
            return self.HexToDec(self.getReg(DS1307_REG_MONTH))
        else:
            self.setReg(DS1307_REG_MONTH, self.DecToHex(month%13))
            
    def Day(self, day = None):
        if day == None:
            return self.HexToDec(self.getReg(DS1307_REG_DAY))
        else:
            self.setReg(DS1307_REG_DAY, self.DecToHex(day%32))

    def Weekday(self, weekday = None):
        if weekday == None:
            return self.HexToDec(self.getReg(DS1307_REG_WEEKDAY))
        else:
            self.setReg(DS1307_REG_WEEKDAY, self.DecToHex(weekday%8))

    def Hour(self, hour = None):
        if hour == None:
            return self.HexToDec(self.getReg(DS1307_REG_HOUR))
        else:
            self.setReg(DS1307_REG_HOUR, self.DecToHex(hour%24))

    def Minute(self, minute = None):
        if minute == None:
            return self.HexToDec(self.getReg(DS1307_REG_MINUTE))
        else:
            self.setReg(DS1307_REG_MINUTE, self.DecToHex(minute%60))

    def Second(self, second = None):
        if second == None:
            return self.HexToDec(self.getReg(DS1307_REG_SECOND))
        else:
            self.setReg(DS1307_REG_SECOND, self.DecToHex(second%60))

    def ram(self, reg, dat = None):
        if dat == None:
            return self.getReg(DS1307_REG_RAM + (reg%56))
        else:
            self.setReg(DS1307_REG_RAM + (reg%56), dat)