# Christian Fiot Sep 2021 # RTC - DS1307 # RTC - PCF8523 2.2.28 # # Usage: # ds1307 = DS1307(i2c=I2C1, traceDebug=True) # pcf8523 = PCF8523(i2c=I2C1, traceDebug=True) # In the following example replace RTC by ds1307 or pcf8523 # # RTC.begin() # # !!! Beware ds1307 requires one additional parameter weekday# !!! # ds1307.datetime( datetime=(year,month,day,weekday#,hour,min,sec)) ...set time # pcf8523.datetime( datetime=(2021,09,29,14,32,0)) ...weekday is not used # # RTC.datetime() read time # from trap import * from machine import I2C class PCF8523(): # 2.2.28 same adr as DS1307 def __init__(self, iicadr=0x068, i2c=None, sda='P22', scl='P21', traceDebug=False, sdAccess=False): self.trace = traceDebug self.adr = iicadr self.sdAccess = sdAccess self.data = bytearray(1) self.weekday_start = 1 # I2C bus declaration is extenal # PCA is connected on I2C bus #1 SDA-P22 SCL-P21 if i2c is not None: self.i2c1 = i2c else: # from machine import I2C self.i2c1 = I2C(0, mode=I2C.MASTER, pins=(sda, scl)) def begin(self): try: self.data[0] = 0x10 # reset + 24h self.i2c1.writeto_mem(self.adr, 0, self.data) # write to Ctrl_1 self.data[0] = 0x00 # battery switch-over enabled in standard mode, battery low detection enabled self.i2c1.writeto_mem(self.adr, 2, self.data) # write to Ctrl_3 print('Detected RTC PCF8523 Adr:' + str(self.adr)) return True except Exception as e: scratch = 'RTC PCF8523 Adr:' + str(self.adr) + ' not found - ' file_errLog(0, scratch + str(e), self.sdAccess) return False def _dec2bcd(self, value): # Convert decimal to binary coded decimal (BCD) format return (value // 10) << 4 | (value % 10) def _bcd2dec(self, value): # Convert binary coded decimal (BCD) format to decimal return ((value >> 4) * 10) + (value & 0x0F) # 2.2.28 weekday# is not used datetime=(year,month,day,hour,min,sec)) def datetime(self, datetime=None): # Get or set datetime if datetime is None: buf = self.i2c1.readfrom_mem(self.adr, 3, 7) return ( self._bcd2dec(buf[6]) + 2000, # year self._bcd2dec(buf[5]), # month # 2.2.28 self._bcd2dec(buf[4] - self.weekday_start), # weekday self._bcd2dec(buf[3]), # day self._bcd2dec(buf[2]), # hour self._bcd2dec(buf[1]), # minute self._bcd2dec(buf[0] & 0x7F), # second 0, # microsecond None # Timezone ) buf = bytearray(7) buf[0] = self._dec2bcd(datetime[5]) & 0x7F # second, msb = CH, 1=halt, 0=go buf[1] = self._dec2bcd(datetime[4]) # minute buf[2] = self._dec2bcd(datetime[3]) # hour buf[3] = self._dec2bcd(datetime[2]) # day buf[4] = 1 # 2.2.28 buf[4] = self._dec2bcd(datetime[3] + self.weekday_start) # weekday buf[5] = self._dec2bcd(datetime[1]) # month buf[6] = self._dec2bcd(datetime[0] - 2000) # year self.i2c1.writeto_mem(self.adr, 3, buf) print('Set RTC PCF8523 time') # DS1307 internal register DATETIME_REG = const(0) # 0x00-0x06 CHIP_HALT = const(128) CONTROL_REG = const(7) # 0x07 RAM_REG = const(8) # 0x08-0x3F class DS1307(): # 2.2.27 def __init__(self, iicadr=0x068, i2c=None, sda='P22', scl='P21', traceDebug=False, sdAccess=False): self.trace = traceDebug self.adr = iicadr self.sdAccess = sdAccess self.data = bytearray(1) self.weekday_start = 1 self._halt = False # I2C bus declaration is extenal # PCA is connected on I2C bus #1 SDA-P22 SCL-P21 if i2c is not None: self.i2c1 = i2c else: # from machine import I2C self.i2c1 = I2C(0, mode=I2C.MASTER, pins=(sda, scl)) def begin(self): try: self.halt(False) # enable RTC self.h12format(False) # set time format 24h print('Detected RTC DS1307 Adr:' + str(self.adr)) return True except Exception as e: scratch = 'RTC DS1307 Adr:' + str(self.adr) + ' not found - ' file_errLog(0, scratch + str(e), self.sdAccess) return False def _dec2bcd(self, value): # Convert decimal to binary coded decimal (BCD) format return (value // 10) << 4 | (value % 10) def _bcd2dec(self, value): # Convert binary coded decimal (BCD) format to decimal return ((value >> 4) * 10) + (value & 0x0F) # datetime=(year,month,day,weekday#,hour,min,sec) # datetime=(2021,09,29,4,14,32,0)) def datetime(self, datetime=None): # Get or set datetime if datetime is None: buf = self.i2c1.readfrom_mem(self.adr, DATETIME_REG, 7) return ( self._bcd2dec(buf[6]) + 2000, # year self._bcd2dec(buf[5]), # month self._bcd2dec(buf[4]), # day self._bcd2dec(buf[3] - self.weekday_start), # weekday self._bcd2dec(buf[2]), # hour self._bcd2dec(buf[1]), # minute self._bcd2dec(buf[0] & 0x7F) # second ) buf = bytearray(7) buf[0] = self._dec2bcd(datetime[6]) & 0x7F # second, msb = CH, 1=halt, 0=go buf[1] = self._dec2bcd(datetime[5]) # minute buf[2] = self._dec2bcd(datetime[4]) & 0x40 # hour, 24h mode buf[3] = self._dec2bcd(datetime[3] + self.weekday_start) # weekday buf[4] = self._dec2bcd(datetime[2]) # day buf[5] = self._dec2bcd(datetime[1]) # month buf[6] = self._dec2bcd(datetime[0] - 2000) # year if (self._halt): buf[0] |= (1 << 7) self.i2c1.writeto_mem(self.adr, DATETIME_REG, buf) def halt(self, val=None): # Power up=False, power down=True or check status if val is None: return self._halt self.i2c1.readfrom_mem_into(self.adr, 0, self.data) data = self.data[0] if self.trace: print('RTC $00: 0x{0:04X}'.format(data) ) if val: data |= CHIP_HALT else: data &= ~CHIP_HALT self._halt = bool(val) self.data[0] = data self.i2c1.writeto_mem(self.adr, 0, self.data) def h12format(self, val=False): # 1= 12h, 0= 24h mode self.i2c1.readfrom_mem_into(self.adr, 2, self.data) data = self.data[0] if self.trace: print('RTC $02: 0x{0:04X}'.format(data) ) if val: data |= 64 # b6 =1 12h else: data &= ~64 # b6 =0 24h self.data[0] = data self.i2c1.writeto_mem(self.adr, 2, self.data) # sqw = 0,1=1hz,4=4k,8=8k,32=32k def square_wave(self, sqw=0, out=0): # 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. data = self.data[0] # reg = bytearray(1) 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 data = rs0 | rs1 << 1 | sqw << 4 | out << 7 self.data[0] = data self.i2c1.writeto_mem(self.adr, CONTROL_REG, self.data)