Jhon Goez / RTC-DS1307

Working Version of the Real Time Clock module DS1307.

Dependents:   Alarma_rtc

Fork of RTC-DS1307 by Henry Leinen

Rtc_Ds1307.cpp@4:d2cc690aaac7, 2013-06-23 (annotated)

Committer:
leihen
Date:
Sun Jun 23 16:29:35 2013 +0000
Revision:
4:d2cc690aaac7
Parent:
3:e89d63f3342e
Child:
5:30531f2121a2
Added a RTC wrapper class.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
leihen 0:3940f0ad2ca5 1 /* Rtc_Ds1307.cpp */
leihen 0:3940f0ad2ca5 2
leihen 0:3940f0ad2ca5 3 #include "Rtc_Ds1307.h"
leihen 4:d2cc690aaac7 4 //#define DEBUG
leihen 4:d2cc690aaac7 5 #undef DEBUG
leihen 3:e89d63f3342e 6 #include "debug.h"
leihen 0:3940f0ad2ca5 7
leihen 1:64274190e842 8 const char *Rtc_Ds1307::m_weekDays[] = { "Saturday", "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday" };
leihen 0:3940f0ad2ca5 9
leihen 0:3940f0ad2ca5 10
leihen 0:3940f0ad2ca5 11 Rtc_Ds1307::Rtc_Ds1307(PinName sda, PinName scl)
leihen 0:3940f0ad2ca5 12 {
leihen 0:3940f0ad2ca5 13 // Create a new I2C object
leihen 0:3940f0ad2ca5 14 m_rtc = new I2C(sda, scl);
leihen 0:3940f0ad2ca5 15 if (m_rtc == NULL)
leihen 0:3940f0ad2ca5 16 error("Rtc_Ds1307");
leihen 1:64274190e842 17
leihen 1:64274190e842 18 // Set the frequency to standard 100kHz
leihen 1:64274190e842 19 m_rtc->frequency(100000);
leihen 0:3940f0ad2ca5 20 }
leihen 0:3940f0ad2ca5 21
leihen 0:3940f0ad2ca5 22 Rtc_Ds1307::~Rtc_Ds1307()
leihen 0:3940f0ad2ca5 23 {
leihen 0:3940f0ad2ca5 24 if (m_rtc != NULL)
leihen 0:3940f0ad2ca5 25 delete m_rtc;
leihen 0:3940f0ad2ca5 26 }
leihen 0:3940f0ad2ca5 27
leihen 1:64274190e842 28 bool Rtc_Ds1307::setTime(Time& time, bool start, bool thm)
leihen 0:3940f0ad2ca5 29 {
leihen 2:ee81f2c5a706 30 char buffer[7];
leihen 2:ee81f2c5a706 31 INFO("reading clock registers to write the new time : %d:%d:%d\n", time.hour, time.min, time.sec);
leihen 2:ee81f2c5a706 32 if (!read(0,buffer,7)) {
leihen 2:ee81f2c5a706 33 ERR("Failed to read from RTC\n");
leihen 2:ee81f2c5a706 34 return false;
leihen 2:ee81f2c5a706 35 }
leihen 2:ee81f2c5a706 36 // Now update only the time part (saving the existing flags)
leihen 2:ee81f2c5a706 37 if (start) { buffer[0] &= 0x7F; } else { buffer[0] |= 0x80; }
leihen 2:ee81f2c5a706 38 buffer[0] = (buffer[0]&0x80) | (decimalToBcd(time.sec)& 0x7f);
leihen 2:ee81f2c5a706 39 buffer[1] = decimalToBcd(time.min);
leihen 2:ee81f2c5a706 40 if (thm) {
leihen 2:ee81f2c5a706 41 // AM PM format
leihen 2:ee81f2c5a706 42 buffer[2] = (buffer[2]& 196) | (time.hour>12 ? (0x20 | ((decimalToBcd(time.hour-12)))) : decimalToBcd(time.hour));
leihen 2:ee81f2c5a706 43 }
leihen 2:ee81f2c5a706 44 else {
leihen 2:ee81f2c5a706 45 // 24 hours format
leihen 2:ee81f2c5a706 46 buffer[2] = (buffer[2]& 196) | (decimalToBcd(time.hour) & 0x3F);
leihen 2:ee81f2c5a706 47 }
leihen 2:ee81f2c5a706 48 buffer[3] = time.wday;
leihen 2:ee81f2c5a706 49 buffer[4] = decimalToBcd(time.date);
leihen 2:ee81f2c5a706 50 buffer[5] = decimalToBcd(time.mon);
leihen 2:ee81f2c5a706 51 buffer[6] = decimalToBcd(time.year-2000);
leihen 2:ee81f2c5a706 52 INFO("Writing new time and date data to RTC\n");
leihen 2:ee81f2c5a706 53 if (!write(0, buffer, 7) ) {
leihen 2:ee81f2c5a706 54 ERR("Failed to write the data to RTC!\n");
leihen 2:ee81f2c5a706 55 return false;
leihen 2:ee81f2c5a706 56 }
leihen 0:3940f0ad2ca5 57 return true;
leihen 0:3940f0ad2ca5 58 }
leihen 0:3940f0ad2ca5 59
leihen 1:64274190e842 60 bool Rtc_Ds1307::getTime(Time& time)
leihen 0:3940f0ad2ca5 61 {
leihen 1:64274190e842 62 char buffer[7];
leihen 1:64274190e842 63 bool thm = false;
leihen 1:64274190e842 64
leihen 1:64274190e842 65 INFO("Getting time from RTC\n");
leihen 2:ee81f2c5a706 66 if (!read(0, buffer, 7) ) {
leihen 1:64274190e842 67 // Failed to read
leihen 1:64274190e842 68 ERR("Failed to read from RTC\n");
leihen 1:64274190e842 69 return false;
leihen 1:64274190e842 70 }
leihen 1:64274190e842 71 thm = ((buffer[2] & 64) == 64);
leihen 1:64274190e842 72 time.sec = bcdToDecimal(buffer[0]&0x7F);
leihen 1:64274190e842 73 time.min = bcdToDecimal(buffer[1]);
leihen 1:64274190e842 74 if (thm) {
leihen 1:64274190e842 75 // in 12-hour-mode, we need to add 12 hours if PM bit is set
leihen 1:64274190e842 76 time.hour = Rtc_Ds1307::bcdToDecimal( buffer[2] & 31 );
leihen 1:64274190e842 77 if ((buffer[2] & 32) == 32)
leihen 1:64274190e842 78 time.hour += 12;
leihen 1:64274190e842 79 }
leihen 1:64274190e842 80 else {
leihen 1:64274190e842 81 time.hour = Rtc_Ds1307::bcdToDecimal( buffer[2] & 63 );
leihen 1:64274190e842 82 }
leihen 1:64274190e842 83 time.wday = buffer[3];
leihen 1:64274190e842 84 time.date = Rtc_Ds1307::bcdToDecimal( buffer[4]);
leihen 1:64274190e842 85 time.mon = Rtc_Ds1307::bcdToDecimal( buffer[5]);
leihen 2:ee81f2c5a706 86 time.year = Rtc_Ds1307::bcdToDecimal(buffer[6]) + 2000; // plus hundret is because RTC is giving the years since 2000, but std c struct tm needs years since 1900
leihen 2:ee81f2c5a706 87
leihen 2:ee81f2c5a706 88 return true;
leihen 2:ee81f2c5a706 89 }
leihen 2:ee81f2c5a706 90
leihen 2:ee81f2c5a706 91
leihen 2:ee81f2c5a706 92 bool Rtc_Ds1307::startClock()
leihen 2:ee81f2c5a706 93 {
leihen 2:ee81f2c5a706 94 char strtStop;
leihen 2:ee81f2c5a706 95
leihen 2:ee81f2c5a706 96 INFO ("Reading clock start/stop register value\n");
leihen 2:ee81f2c5a706 97 if (!read(0, &strtStop, 1)) {
leihen 2:ee81f2c5a706 98 ERR("Failed to read clock start stop register !\n");
leihen 2:ee81f2c5a706 99 return false;
leihen 2:ee81f2c5a706 100 }
leihen 2:ee81f2c5a706 101
leihen 2:ee81f2c5a706 102 strtStop &= 0x7F;
leihen 2:ee81f2c5a706 103
leihen 2:ee81f2c5a706 104 INFO("Writing back start/stop register value\n");
leihen 2:ee81f2c5a706 105 if (!write(0, &strtStop, 1)) {
leihen 2:ee81f2c5a706 106 ERR("Failed to write the start stop register !\n");
leihen 2:ee81f2c5a706 107 return false;
leihen 2:ee81f2c5a706 108 }
leihen 2:ee81f2c5a706 109
leihen 2:ee81f2c5a706 110 INFO("Start/stop register value successfully written\n");
leihen 2:ee81f2c5a706 111 return true;
leihen 2:ee81f2c5a706 112 }
leihen 2:ee81f2c5a706 113
leihen 2:ee81f2c5a706 114 bool Rtc_Ds1307::stopClock()
leihen 2:ee81f2c5a706 115 {
leihen 2:ee81f2c5a706 116 char strtStop;
leihen 2:ee81f2c5a706 117
leihen 2:ee81f2c5a706 118 INFO ("Reading clock start/stop register value\n");
leihen 2:ee81f2c5a706 119 if (!read(0, &strtStop, 1)) {
leihen 2:ee81f2c5a706 120 ERR("Failed to read clock start stop register !\n");
leihen 2:ee81f2c5a706 121 return false;
leihen 2:ee81f2c5a706 122 }
leihen 1:64274190e842 123
leihen 2:ee81f2c5a706 124 strtStop |= 0x80;
leihen 2:ee81f2c5a706 125
leihen 2:ee81f2c5a706 126 INFO("Writing back start/stop register value\n");
leihen 2:ee81f2c5a706 127 if (!write(0, &strtStop, 1)) {
leihen 2:ee81f2c5a706 128 ERR("Failed to write the start stop register !\n");
leihen 2:ee81f2c5a706 129 return false;
leihen 2:ee81f2c5a706 130 }
leihen 2:ee81f2c5a706 131
leihen 2:ee81f2c5a706 132 INFO("Start/stop register value successfully written\n");
leihen 2:ee81f2c5a706 133 return true;
leihen 0:3940f0ad2ca5 134 }
leihen 1:64274190e842 135
leihen 2:ee81f2c5a706 136 bool Rtc_Ds1307::setSquareWaveOutput(bool ena, RateSelect_t rs)
leihen 2:ee81f2c5a706 137 {
leihen 2:ee81f2c5a706 138 char reg;
leihen 2:ee81f2c5a706 139 INFO("Reading register value first\n");
leihen 2:ee81f2c5a706 140
leihen 2:ee81f2c5a706 141 if (!read(7,&reg, 1)) {
leihen 2:ee81f2c5a706 142 ERR("Failed to read register value !\n");
leihen 2:ee81f2c5a706 143 return false;
leihen 2:ee81f2c5a706 144 }
leihen 2:ee81f2c5a706 145 INFO("[Reg:0x07] = %02x\n", reg);
leihen 2:ee81f2c5a706 146
leihen 2:ee81f2c5a706 147 // preserve the OUT control bit while writing the frequency and enable bits
leihen 2:ee81f2c5a706 148 reg = (reg & 0x80) | (ena ? 0x10 : 0) | ((char)rs & 0x03);
leihen 2:ee81f2c5a706 149
leihen 2:ee81f2c5a706 150 INFO("Writing back register value\n");
leihen 2:ee81f2c5a706 151 INFO("[Reg:0x07] = %02x\n", reg);
leihen 2:ee81f2c5a706 152
leihen 2:ee81f2c5a706 153 if (!write(7, &reg, 1)) {
leihen 2:ee81f2c5a706 154 ERR("Failed to write register value !\n");
leihen 2:ee81f2c5a706 155 return false;
leihen 2:ee81f2c5a706 156 }
leihen 2:ee81f2c5a706 157
leihen 2:ee81f2c5a706 158 INFO("Successfully changed the square wave output.\n");
leihen 2:ee81f2c5a706 159 return true;
leihen 2:ee81f2c5a706 160 }
leihen 2:ee81f2c5a706 161
leihen 2:ee81f2c5a706 162
leihen 1:64274190e842 163
leihen 1:64274190e842 164 bool Rtc_Ds1307::read(int address, char *buffer, int len)
leihen 1:64274190e842 165 {
leihen 1:64274190e842 166 char buffer2[2] = {(char)address, 0};
leihen 1:64274190e842 167
leihen 2:ee81f2c5a706 168 // m_rtc->start();
leihen 1:64274190e842 169 if (m_rtc->write(0xd0, buffer2, 1) != 0) {
leihen 1:64274190e842 170 ERR("Failed to write register address on rtv!\n");
leihen 1:64274190e842 171 m_rtc->stop();
leihen 1:64274190e842 172 return false;
leihen 1:64274190e842 173 }
leihen 1:64274190e842 174 if (m_rtc->read(0xd0, buffer, len) != 0) {
leihen 1:64274190e842 175 ERR("Failed to read register !\n");
leihen 1:64274190e842 176 return false;
leihen 1:64274190e842 177 }
leihen 1:64274190e842 178 m_rtc->stop();
leihen 1:64274190e842 179
leihen 1:64274190e842 180 INFO("Successfully read %d registers from RTC\n", len);
leihen 1:64274190e842 181 return true;
leihen 1:64274190e842 182 }
leihen 1:64274190e842 183
leihen 1:64274190e842 184 bool Rtc_Ds1307::write(int address, char *buffer, int len)
leihen 1:64274190e842 185 {
leihen 1:64274190e842 186 char buffer2[10];
leihen 1:64274190e842 187 buffer2[0] = address&0xFF;
leihen 1:64274190e842 188 for (int i = 0 ; i < len ; i++)
leihen 1:64274190e842 189 buffer2[i+1] = buffer[i];
leihen 1:64274190e842 190
leihen 2:ee81f2c5a706 191 // m_rtc->start();
leihen 1:64274190e842 192 if (m_rtc->write(0xd0, buffer2, len+1) != 0) {
leihen 1:64274190e842 193 ERR("Failed to write data to rtc\n");
leihen 1:64274190e842 194 m_rtc->stop();
leihen 1:64274190e842 195 return false;
leihen 1:64274190e842 196 }
leihen 1:64274190e842 197 m_rtc->stop();
leihen 1:64274190e842 198 return true;
leihen 1:64274190e842 199 }