Feng Hong / DS3231

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DS3231.cpp@0:084c63e7e80d, 2019-10-19 (annotated)

Committer:
hi1000
Date:
Sat Oct 19 02:09:39 2019 +0000
Revision:
0:084c63e7e80d
The first version of ROT-CANBUS R01/00819

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hi1000 0:084c63e7e80d 1 #include "DS3231.h"
hi1000 0:084c63e7e80d 2
hi1000 0:084c63e7e80d 3 DS3231::DS3231(PinName sda, PinName scl) : i2c(sda, scl)
hi1000 0:084c63e7e80d 4 {
hi1000 0:084c63e7e80d 5 }
hi1000 0:084c63e7e80d 6
hi1000 0:084c63e7e80d 7
hi1000 0:084c63e7e80d 8 // BCD to decimal conversion
hi1000 0:084c63e7e80d 9 int DS3231::bcd2dec(int k)
hi1000 0:084c63e7e80d 10 {return(((k&0xF0)>>4)*10+(k&0x0F));}
hi1000 0:084c63e7e80d 11
hi1000 0:084c63e7e80d 12
hi1000 0:084c63e7e80d 13 // decimal to BCD conversion
hi1000 0:084c63e7e80d 14 int DS3231::dec2bcd(int k)
hi1000 0:084c63e7e80d 15 {return((k/10)*16+(k%10));}
hi1000 0:084c63e7e80d 16
hi1000 0:084c63e7e80d 17 void DS3231::setI2Cfrequency(int frequency)
hi1000 0:084c63e7e80d 18 {i2c.frequency(frequency);
hi1000 0:084c63e7e80d 19 }
hi1000 0:084c63e7e80d 20
hi1000 0:084c63e7e80d 21 // read temperature from DS3231
hi1000 0:084c63e7e80d 22 float DS3231::readTemp()
hi1000 0:084c63e7e80d 23 {char buf[2];
hi1000 0:084c63e7e80d 24 buf[0]=DS3231_MSB_Temp;
hi1000 0:084c63e7e80d 25 int w=i2c.write(DS3231_Address,buf,1);
hi1000 0:084c63e7e80d 26 int r=i2c.read(DS3231_Address,buf,2);
hi1000 0:084c63e7e80d 27 error=((w!=0)||(r!=0));
hi1000 0:084c63e7e80d 28 return(buf[0]+buf[1]/256.0);}
hi1000 0:084c63e7e80d 29
hi1000 0:084c63e7e80d 30 // force temperatue conversion
hi1000 0:084c63e7e80d 31 void DS3231::convertTemperature()
hi1000 0:084c63e7e80d 32 {
hi1000 0:084c63e7e80d 33 int Control=readRegister(DS3231_Control)|DS3231_bit_CONV;
hi1000 0:084c63e7e80d 34 writeRegister(DS3231_Control,Control);
hi1000 0:084c63e7e80d 35 }
hi1000 0:084c63e7e80d 36
hi1000 0:084c63e7e80d 37 // decode time registers
hi1000 0:084c63e7e80d 38 void DS3231::decodeTime(int regHours, int regMinutes, int regSeconds,int *Hours, int *Minutes, int *Seconds)
hi1000 0:084c63e7e80d 39 {
hi1000 0:084c63e7e80d 40 *Hours=bcd2dec(regHours);
hi1000 0:084c63e7e80d 41 *Minutes=bcd2dec(regMinutes);
hi1000 0:084c63e7e80d 42 *Seconds=bcd2dec(regSeconds);
hi1000 0:084c63e7e80d 43 }
hi1000 0:084c63e7e80d 44
hi1000 0:084c63e7e80d 45
hi1000 0:084c63e7e80d 46 // read time registers dand decode them to decimal
hi1000 0:084c63e7e80d 47 void DS3231::readTime(int *hours, int *minutes, int *seconds)
hi1000 0:084c63e7e80d 48 {
hi1000 0:084c63e7e80d 49 char buf[3];
hi1000 0:084c63e7e80d 50 buf[0]=DS3231_Seconds;
hi1000 0:084c63e7e80d 51 int w=i2c.write(DS3231_Address,buf,1);
hi1000 0:084c63e7e80d 52 int r=i2c.read(DS3231_Address,buf,3);
hi1000 0:084c63e7e80d 53 decodeTime(buf[2],buf[1],buf[0],hours,minutes,seconds);
hi1000 0:084c63e7e80d 54 error=((w!=0)||(r!=0));
hi1000 0:084c63e7e80d 55 }
hi1000 0:084c63e7e80d 56
hi1000 0:084c63e7e80d 57 // set time register
hi1000 0:084c63e7e80d 58 void DS3231::setTime(int hours, int minutes, int seconds)
hi1000 0:084c63e7e80d 59 {
hi1000 0:084c63e7e80d 60 writeRegister(DS3231_Seconds,dec2bcd(seconds));
hi1000 0:084c63e7e80d 61 writeRegister(DS3231_Minutes,dec2bcd(minutes));
hi1000 0:084c63e7e80d 62 writeRegister(DS3231_Hours,dec2bcd(hours));
hi1000 0:084c63e7e80d 63 }
hi1000 0:084c63e7e80d 64
hi1000 0:084c63e7e80d 65 // decode date registers
hi1000 0:084c63e7e80d 66 void DS3231::decodeDate(int regDate,int regMonth, int regYear, int *date, int *month, int *year)
hi1000 0:084c63e7e80d 67 {
hi1000 0:084c63e7e80d 68 *date=bcd2dec(regDate);
hi1000 0:084c63e7e80d 69 int century=regMonth&128;
hi1000 0:084c63e7e80d 70 *month=bcd2dec(regMonth&127);
hi1000 0:084c63e7e80d 71 *year=bcd2dec(regYear);
hi1000 0:084c63e7e80d 72 if (century==0) // only XXth and XXIst centuries allowed
hi1000 0:084c63e7e80d 73 {*year=*year+1900;}
hi1000 0:084c63e7e80d 74 else
hi1000 0:084c63e7e80d 75 {*year=*year+2000;}
hi1000 0:084c63e7e80d 76 }
hi1000 0:084c63e7e80d 77
hi1000 0:084c63e7e80d 78 // read date registers
hi1000 0:084c63e7e80d 79 void DS3231::readDate(int *date, int *month, int *year)
hi1000 0:084c63e7e80d 80 {
hi1000 0:084c63e7e80d 81 char buf[3];
hi1000 0:084c63e7e80d 82 buf[0]=DS3231_Date;
hi1000 0:084c63e7e80d 83 int w=i2c.write(DS3231_Address,buf,1);
hi1000 0:084c63e7e80d 84 int r=i2c.read(DS3231_Address,buf,3);
hi1000 0:084c63e7e80d 85 decodeDate(buf[0],buf[1],buf[2],date,month,year);
hi1000 0:084c63e7e80d 86 error=((w!=0)||(r!=0));
hi1000 0:084c63e7e80d 87 }
hi1000 0:084c63e7e80d 88
hi1000 0:084c63e7e80d 89 // set the date registers
hi1000 0:084c63e7e80d 90 void DS3231::setDate(int dayOfWeek, int date, int month, int year)
hi1000 0:084c63e7e80d 91 {
hi1000 0:084c63e7e80d 92 writeRegister(DS3231_Date,dec2bcd(date));
hi1000 0:084c63e7e80d 93 writeRegister(DS3231_Day,dayOfWeek);
hi1000 0:084c63e7e80d 94 int century=0; // only XXth and XXIst centuries allowed
hi1000 0:084c63e7e80d 95 if (year<1900){year=1900;}
hi1000 0:084c63e7e80d 96 if (year>2099){year=2099;}
hi1000 0:084c63e7e80d 97 if (year<2000)
hi1000 0:084c63e7e80d 98 {year=year-1900;}
hi1000 0:084c63e7e80d 99 else
hi1000 0:084c63e7e80d 100 {year=year-2000;century=1;}
hi1000 0:084c63e7e80d 101 writeRegister(DS3231_Month_Century,dec2bcd(month)+128*century);
hi1000 0:084c63e7e80d 102 writeRegister(DS3231_Year,dec2bcd(year));
hi1000 0:084c63e7e80d 103 }
hi1000 0:084c63e7e80d 104
hi1000 0:084c63e7e80d 105 // read date and time registers
hi1000 0:084c63e7e80d 106 void DS3231::readDateTime(int *dayOfWeek, int *date, int *month, int *year, int *hours, int *minutes, int *seconds)
hi1000 0:084c63e7e80d 107 {
hi1000 0:084c63e7e80d 108 char buf[7];
hi1000 0:084c63e7e80d 109 buf[0]=DS3231_Seconds;
hi1000 0:084c63e7e80d 110 int w=i2c.write(DS3231_Address,buf,1);
hi1000 0:084c63e7e80d 111 int r=i2c.read(DS3231_Address,buf,7);
hi1000 0:084c63e7e80d 112 decodeTime(buf[2],buf[1],buf[0],hours,minutes,seconds);
hi1000 0:084c63e7e80d 113 *dayOfWeek=buf[3];
hi1000 0:084c63e7e80d 114 decodeDate(buf[4],buf[5],buf[6],date,month,year);
hi1000 0:084c63e7e80d 115 error=((w!=0)||(r!=0));
hi1000 0:084c63e7e80d 116 }
hi1000 0:084c63e7e80d 117
hi1000 0:084c63e7e80d 118 // read a register
hi1000 0:084c63e7e80d 119 int DS3231::readRegister(char reg)
hi1000 0:084c63e7e80d 120 {
hi1000 0:084c63e7e80d 121 char buf[1];
hi1000 0:084c63e7e80d 122 buf[0]=reg;
hi1000 0:084c63e7e80d 123 int w=i2c.write(DS3231_Address,buf,1);
hi1000 0:084c63e7e80d 124 int r=i2c.read(DS3231_Address,buf,1);
hi1000 0:084c63e7e80d 125 error=((w!=0)||(r!=0));
hi1000 0:084c63e7e80d 126 return(buf[0]);
hi1000 0:084c63e7e80d 127 }
hi1000 0:084c63e7e80d 128
hi1000 0:084c63e7e80d 129 // write a register
hi1000 0:084c63e7e80d 130 void DS3231::writeRegister(int reg,char byte)
hi1000 0:084c63e7e80d 131 {
hi1000 0:084c63e7e80d 132 char buf[2];
hi1000 0:084c63e7e80d 133 buf[0]=reg;
hi1000 0:084c63e7e80d 134 buf[1]=byte;
hi1000 0:084c63e7e80d 135 int w=i2c.write(DS3231_Address,buf,2);
hi1000 0:084c63e7e80d 136 error=(w!=0);
hi1000 0:084c63e7e80d 137 }
hi1000 0:084c63e7e80d 138
hi1000 0:084c63e7e80d 139 void DS3231::eraseOSF()
hi1000 0:084c63e7e80d 140 {
hi1000 0:084c63e7e80d 141 int reg=readRegister(DS3231_Control_Status);
hi1000 0:084c63e7e80d 142 reg=reg&0x7F;
hi1000 0:084c63e7e80d 143 writeRegister(DS3231_Control_Status,reg);
hi1000 0:084c63e7e80d 144 }
hi1000 0:084c63e7e80d 145
hi1000 0:084c63e7e80d 146 bool DS3231::OSF()
hi1000 0:084c63e7e80d 147 {
hi1000 0:084c63e7e80d 148 int reg=readRegister(DS3231_Control_Status);
hi1000 0:084c63e7e80d 149 return(reg&DS3231_bit_OSF);
hi1000 0:084c63e7e80d 150 }