remi cormier / DS3231

MAXIM DS3231 accurate Real Time Clock Library

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DS3231.h@2:6718c4fabf95, 2012-12-22 (annotated)

Committer:
cromda
Date:
Sat Dec 22 19:58:42 2012 +0000
Revision:
2:6718c4fabf95
Parent:
1:84ccc64067d8 
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cromda 0:11dfd7ac4188 1 /** mbded library for driving the PMAXIM DS3231 Real Time Clock
cromda 0:11dfd7ac4188 2 * datasheet link : http://datasheets.maximintegrated.com/en/ds/DS3231.pdf
cromda 0:11dfd7ac4188 3 * breakout : MACETECH ChronoDot V2.1 High Precision RTC
cromda 0:11dfd7ac4188 4 * remi cormier 2012
cromda 0:11dfd7ac4188 5 * WARNING : sda and sdl should be pulled up with 2.2k resistor
cromda 0:11dfd7ac4188 6 */
cromda 0:11dfd7ac4188 7
cromda 0:11dfd7ac4188 8 /** Example code
cromda 0:11dfd7ac4188 9 * @code
cromda 0:11dfd7ac4188 10 // DS3231 Library test program
cromda 0:11dfd7ac4188 11 // remi cormier 2012
cromda 0:11dfd7ac4188 12
cromda 0:11dfd7ac4188 13 #include "mbed.h"
cromda 0:11dfd7ac4188 14 #include "DS3231.h"
cromda 0:11dfd7ac4188 15
cromda 0:11dfd7ac4188 16 Serial pc(USBTX, USBRX);
cromda 0:11dfd7ac4188 17
cromda 0:11dfd7ac4188 18 int hour;
cromda 0:11dfd7ac4188 19 int minute;
cromda 0:11dfd7ac4188 20 int second;
cromda 0:11dfd7ac4188 21
cromda 0:11dfd7ac4188 22 int dayOfWeek;
cromda 0:11dfd7ac4188 23 int date;
cromda 0:11dfd7ac4188 24 int month;
cromda 0:11dfd7ac4188 25 int year;
cromda 0:11dfd7ac4188 26
cromda 0:11dfd7ac4188 27 DS3231 RTC(p28,p27);
cromda 0:11dfd7ac4188 28
cromda 0:11dfd7ac4188 29
cromda 0:11dfd7ac4188 30 int main()
cromda 0:11dfd7ac4188 31 {printf("\r\n\nDS3231 Library test program\r\nremi cormier 2012\r\n\n");
cromda 0:11dfd7ac4188 32
cromda 0:11dfd7ac4188 33 RTC.setI2Cfrequency(400000);
cromda 0:11dfd7ac4188 34
cromda 0:11dfd7ac4188 35 //RTC.writeRegister(DS3231_Aging_Offset,0); // uncomment to set Aging Offset 1LSB = approx. 0.1 ppm according from datasheet = 0.05 ppm @ 21 °C from my measurments
cromda 2:6718c4fabf95 36
cromda 2:6718c4fabf95 37 RTC.convertTemperature();
cromda 0:11dfd7ac4188 38
cromda 0:11dfd7ac4188 39 int reg=RTC.readRegister(DS3231_Aging_Offset);
cromda 0:11dfd7ac4188 40 if (reg>127)
cromda 0:11dfd7ac4188 41 {reg=reg-256;}
cromda 0:11dfd7ac4188 42 pc.printf("Aging offset : %i\r\n",reg);
cromda 0:11dfd7ac4188 43
cromda 0:11dfd7ac4188 44 pc.printf("OSF flag : %i",RTC.OSF());
cromda 0:11dfd7ac4188 45 pc.printf("\r\n");
cromda 0:11dfd7ac4188 46
cromda 0:11dfd7ac4188 47 RTC.readDate(&date,&month,&year);
cromda 0:11dfd7ac4188 48 pc.printf("date : %02i-%02i-%02i",date,month,year);
cromda 0:11dfd7ac4188 49 pc.printf("\r\n");
cromda 0:11dfd7ac4188 50
cromda 0:11dfd7ac4188 51 //RTC.setTime(19,48,45); // uncomment to set time
cromda 0:11dfd7ac4188 52
cromda 0:11dfd7ac4188 53 RTC.readTime(&hour,&minute,&second);
cromda 0:11dfd7ac4188 54 pc.printf("time : %02i:%02i:%02i",hour,minute,second);
cromda 0:11dfd7ac4188 55 pc.printf("\r\n");
cromda 0:11dfd7ac4188 56
cromda 0:11dfd7ac4188 57 //RTC.setDate(6,22,12,2012); // uncomment to set date
cromda 0:11dfd7ac4188 58
cromda 0:11dfd7ac4188 59 RTC.readDateTime(&dayOfWeek,&date,&month,&year,&hour,&minute,&second);
cromda 0:11dfd7ac4188 60 pc.printf("date time : %i / %02i-%02i-%02i %02i:%02i:%02i",dayOfWeek,date,month,year,hour,minute,second);
cromda 0:11dfd7ac4188 61 pc.printf("\r\n");
cromda 0:11dfd7ac4188 62
cromda 0:11dfd7ac4188 63 pc.printf("temperature :%6.2f",RTC.readTemp());
cromda 0:11dfd7ac4188 64 pc.printf("\r\n");
cromda 0:11dfd7ac4188 65 }
cromda 0:11dfd7ac4188 66 * @endcode
cromda 0:11dfd7ac4188 67 */
cromda 0:11dfd7ac4188 68
cromda 0:11dfd7ac4188 69
cromda 0:11dfd7ac4188 70 #include "mbed.h"
cromda 0:11dfd7ac4188 71
cromda 0:11dfd7ac4188 72 #ifndef MBED_DS3231_H
cromda 0:11dfd7ac4188 73 #define MBED_DS3231_H
cromda 0:11dfd7ac4188 74
cromda 0:11dfd7ac4188 75 //DS3231 8 bit adress
cromda 0:11dfd7ac4188 76 #define DS3231_Address 0xD0
cromda 0:11dfd7ac4188 77
cromda 0:11dfd7ac4188 78 //DS3231 registers
cromda 0:11dfd7ac4188 79 #define DS3231_Seconds 0x00
cromda 0:11dfd7ac4188 80 #define DS3231_Minutes 0x01
cromda 0:11dfd7ac4188 81 #define DS3231_Hours 0x02
cromda 0:11dfd7ac4188 82 // DS3231 Hours bits
cromda 0:11dfd7ac4188 83 #define DS3231_bit_AM_PM 0x20
cromda 0:11dfd7ac4188 84 #define DS3231_bit_12_24 0x40
cromda 0:11dfd7ac4188 85
cromda 0:11dfd7ac4188 86 #define DS3231_Day 0x03
cromda 0:11dfd7ac4188 87 #define DS3231_Date 0x04
cromda 0:11dfd7ac4188 88 #define DS3231_Month_Century 0x05
cromda 0:11dfd7ac4188 89 #define DS3231_Year 0x06
cromda 0:11dfd7ac4188 90 #define DS3231_Alarm1_Seconds 0x07
cromda 0:11dfd7ac4188 91 #define DS3231_Alarm1_Minutes 0x08
cromda 0:11dfd7ac4188 92 #define DS3231_Alarm1_Hours 0x09
cromda 0:11dfd7ac4188 93 #define DS3231_Alarm1_Day_Date 0x0A
cromda 0:11dfd7ac4188 94 #define DS3231_Alarm2_Minutes 0x0B
cromda 0:11dfd7ac4188 95 #define DS3231_Alarm2_Hours 0x0C
cromda 0:11dfd7ac4188 96 #define DS3231_Alarm_2_Day_Date 0x0D
cromda 0:11dfd7ac4188 97
cromda 0:11dfd7ac4188 98 #define DS3231_Control 0x0E
cromda 0:11dfd7ac4188 99 // DS3231 Control bits
cromda 0:11dfd7ac4188 100 #define DS3231_bit_A1IE 1
cromda 0:11dfd7ac4188 101 #define DS3231_bit_A2IE 2
cromda 0:11dfd7ac4188 102 #define DS3231_bit_INTCN 4
cromda 0:11dfd7ac4188 103 #define DS3231_bit_SQW_1Hz 0
cromda 0:11dfd7ac4188 104 #define DS3231_bit_SQW_1024Hz 8
cromda 0:11dfd7ac4188 105 #define DS3231_bit_SQW_4096Hz 16
cromda 0:11dfd7ac4188 106 #define DS3231_bit_SQW_8192Hz 24
cromda 0:11dfd7ac4188 107 #define DS3231_bit_CONV 32
cromda 0:11dfd7ac4188 108 #define DS3231_bit_BBSQW 64
cromda 0:11dfd7ac4188 109 #define DS3231_bit_EOSCb 128
cromda 0:11dfd7ac4188 110
cromda 0:11dfd7ac4188 111
cromda 0:11dfd7ac4188 112 #define DS3231_Control_Status 0x0F
cromda 0:11dfd7ac4188 113 // DS3231 Control/Status bits
cromda 0:11dfd7ac4188 114 #define DS3231_bit_BSY 0x04
cromda 0:11dfd7ac4188 115 #define DS3231_bit_EN32kHz 0x08
cromda 0:11dfd7ac4188 116 #define DS3231_bit_OSF 0x80
cromda 0:11dfd7ac4188 117
cromda 0:11dfd7ac4188 118 #define DS3231_Aging_Offset 0x10
cromda 0:11dfd7ac4188 119 #define DS3231_MSB_Temp 0x11
cromda 0:11dfd7ac4188 120 #define DS3231_LSB_Temp 0x12
cromda 0:11dfd7ac4188 121
cromda 0:11dfd7ac4188 122 /* Interface to MAXIM DS3231 RTC */
cromda 0:11dfd7ac4188 123 class DS3231
cromda 0:11dfd7ac4188 124 {public :
cromda 0:11dfd7ac4188 125 /** Create an instance of the DS3231 connected to specfied I2C pins
cromda 0:11dfd7ac4188 126 *
cromda 0:11dfd7ac4188 127 * @param sda The I2C data pin
cromda 0:11dfd7ac4188 128 * @param scl The I2C clock pin
cromda 0:11dfd7ac4188 129 */
cromda 0:11dfd7ac4188 130 DS3231(PinName sda, PinName scl);
cromda 0:11dfd7ac4188 131
cromda 0:11dfd7ac4188 132 /** set I2C bus speed
cromda 0:11dfd7ac4188 133 * @param frequency : I2C clocl frequenct (Hz)
cromda 0:11dfd7ac4188 134 */
cromda 0:11dfd7ac4188 135 void setI2Cfrequency(int frequency);
cromda 0:11dfd7ac4188 136
cromda 0:11dfd7ac4188 137 /** Read the temperature
cromda 0:11dfd7ac4188 138 *
cromda 0:11dfd7ac4188 139 * @return The temperature
cromda 0:11dfd7ac4188 140 */
cromda 0:11dfd7ac4188 141 float readTemp();
cromda 0:11dfd7ac4188 142
cromda 0:11dfd7ac4188 143 /** Read the time registers
cromda 0:11dfd7ac4188 144 * @param hours
cromda 0:11dfd7ac4188 145 * @param minutes
cromda 0:11dfd7ac4188 146 * @param seconds
cromda 0:11dfd7ac4188 147 */
cromda 0:11dfd7ac4188 148 void readTime(int *hours, int *minutes, int *seconds);
cromda 0:11dfd7ac4188 149
cromda 1:84ccc64067d8 150 /** force temperature conversion
cromda 1:84ccc64067d8 151 *
cromda 1:84ccc64067d8 152 */
cromda 1:84ccc64067d8 153 void convertTemperature();
cromda 0:11dfd7ac4188 154
cromda 0:11dfd7ac4188 155 /** Set the time registers
cromda 0:11dfd7ac4188 156 * @param hours
cromda 0:11dfd7ac4188 157 * @param minutes
cromda 0:11dfd7ac4188 158 * @param seconds
cromda 0:11dfd7ac4188 159 */
cromda 0:11dfd7ac4188 160 void setTime(int hours, int minutes, int seconds);
cromda 0:11dfd7ac4188 161
cromda 0:11dfd7ac4188 162 /** Read the date registers
cromda 0:11dfd7ac4188 163 * @param date
cromda 0:11dfd7ac4188 164 * @param month
cromda 0:11dfd7ac4188 165 * @param year
cromda 0:11dfd7ac4188 166 */
cromda 0:11dfd7ac4188 167 void readDate(int *date, int *month, int *year);
cromda 0:11dfd7ac4188 168
cromda 0:11dfd7ac4188 169 /** Set the date registers
cromda 0:11dfd7ac4188 170 * @param dayOfWeek : day of week
cromda 0:11dfd7ac4188 171 * @param date
cromda 0:11dfd7ac4188 172 * @param month
cromda 0:11dfd7ac4188 173 * @param year
cromda 0:11dfd7ac4188 174 */
cromda 0:11dfd7ac4188 175 void setDate(int dayOfWeek, int date, int month, int year);
cromda 0:11dfd7ac4188 176
cromda 0:11dfd7ac4188 177 /** Read the date and time registers
cromda 0:11dfd7ac4188 178 * @param dayOfWeek : day of week
cromda 0:11dfd7ac4188 179 * @param date
cromda 0:11dfd7ac4188 180 * @param month
cromda 0:11dfd7ac4188 181 * @param year
cromda 0:11dfd7ac4188 182 * @param hours
cromda 0:11dfd7ac4188 183 * @param minutes
cromda 0:11dfd7ac4188 184 * @param seconds
cromda 0:11dfd7ac4188 185 */
cromda 0:11dfd7ac4188 186 void readDateTime(int *dayOfWeek, int *date, int *month, int *year, int *hours, int *minutes, int *seconds);
cromda 0:11dfd7ac4188 187
cromda 0:11dfd7ac4188 188 /** Read a register
cromda 0:11dfd7ac4188 189 * @param reg : register address
cromda 0:11dfd7ac4188 190 * @return The register content
cromda 0:11dfd7ac4188 191 */
cromda 0:11dfd7ac4188 192 int readRegister(char reg);
cromda 0:11dfd7ac4188 193
cromda 0:11dfd7ac4188 194 /** Write to a register
cromda 0:11dfd7ac4188 195 * @param reg : register address
cromda 0:11dfd7ac4188 196 * @param The register content
cromda 0:11dfd7ac4188 197 */
cromda 0:11dfd7ac4188 198 void writeRegister(int reg,char byte);
cromda 0:11dfd7ac4188 199
cromda 0:11dfd7ac4188 200 /** set OSF (Oscillator Stop Flag) bit to 0 in Control Status register
cromda 0:11dfd7ac4188 201 * should be done just after power up DS3231
cromda 0:11dfd7ac4188 202 * OSF bit is automaticaly set to 1 when on power up or when the DS3231 oscillator stops
cromda 0:11dfd7ac4188 203 */
cromda 0:11dfd7ac4188 204 void eraseOSF();
cromda 0:11dfd7ac4188 205
cromda 0:11dfd7ac4188 206 /** Return OSF bit. If true the oscillator stopped or the DS3231 just powered up
cromda 0:11dfd7ac4188 207 * @return The OSF bit
cromda 0:11dfd7ac4188 208 */
cromda 0:11dfd7ac4188 209 bool OSF();
cromda 0:11dfd7ac4188 210
cromda 0:11dfd7ac4188 211 bool error;
cromda 0:11dfd7ac4188 212
cromda 0:11dfd7ac4188 213 private :
cromda 0:11dfd7ac4188 214 I2C i2c;
cromda 0:11dfd7ac4188 215 int bcd2dec(int k); // bcd to decimal conversion
cromda 0:11dfd7ac4188 216 int dec2bcd(int k); // decimal to bcd conversion
cromda 0:11dfd7ac4188 217 void decodeTime(int regHours, int regMinutes, int regSeconds,int *Hours, int *Minutes, int *Seconds);
cromda 0:11dfd7ac4188 218 void decodeDate(int regDate,int regMonth, int regYear, int *date, int *month, int *year);
cromda 0:11dfd7ac4188 219 };
cromda 0:11dfd7ac4188 220
cromda 0:11dfd7ac4188 221
cromda 0:11dfd7ac4188 222 #endif