Working Version of the Real Time Clock module DS1307.
Dependents: Rtc_Ds1307_Sample TAREA_5_PROCESADORES Rtc_Ds1307_lcd_alarma Rtc_Ds1307_Reloj_con_alarma_aplazable ... more
This is my implementation of the DS1307.
I plan to add functionality which will make use of the OSC Input and which will increment the time continuously. A query to the module will then only have to be made when the MBED has been powered down.
Rtc_Ds1307.cpp
- Committer:
- leihen
- Date:
- 2013-06-26
- Revision:
- 9:5627b407e097
- Parent:
- 8:d0e66fa78e79
File content as of revision 9:5627b407e097:
#include "mbed.h" #include "Rtc_Ds1307.h" #ifndef DEBUG //#define DEBUG #endif #include "debug.h" const char *Rtc_Ds1307::m_weekDays[] = { "Saturday", "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday" }; Rtc_Ds1307::Rtc_Ds1307(PinName sda, PinName scl) { // Create a new I2C object m_rtc = new I2C(sda, scl); if (m_rtc == NULL) error("Rtc_Ds1307"); // Set the frequency to standard 100kHz m_rtc->frequency(100000); } Rtc_Ds1307::~Rtc_Ds1307() { if (m_rtc != NULL) delete m_rtc; } bool Rtc_Ds1307::setTime(Time_rtc& time, bool start, bool thm) { char buffer[7]; INFO("reading clock registers to write the new time : %d:%d:%d\n", time.hour, time.min, time.sec); if (!read(0,buffer,7)) { ERR("Failed to read from RTC\n"); return false; } // Now update only the time part (saving the existing flags) if (start) { buffer[0] &= 0x7F; } else { buffer[0] |= 0x80; } buffer[0] = (buffer[0]&0x80) | (decimalToBcd(time.sec)& 0x7f); buffer[1] = decimalToBcd(time.min); if (thm) { // AM PM format buffer[2] = (buffer[2]& 196) | (time.hour>12 ? (0x20 | ((decimalToBcd(time.hour-12)))) : decimalToBcd(time.hour)); } else { // 24 hours format buffer[2] = (buffer[2]& 196) | (decimalToBcd(time.hour) & 0x3F); } buffer[3] = time.wday; buffer[4] = decimalToBcd(time.date); buffer[5] = decimalToBcd(time.mon); buffer[6] = decimalToBcd(time.year-2000); INFO("Writing new time and date data to RTC\n"); if (!write(0, buffer, 7) ) { ERR("Failed to write the data to RTC!\n"); return false; } return true; } bool Rtc_Ds1307::getTime(Time_rtc& time) { char buffer[7]; bool thm = false; INFO("Getting time from RTC\n"); if (!read(0, buffer, 7) ) { // Failed to read ERR("Failed to read from RTC\n"); return false; } thm = ((buffer[2] & 64) == 64); time.sec = bcdToDecimal(buffer[0]&0x7F); time.min = bcdToDecimal(buffer[1]); if (thm) { // in 12-hour-mode, we need to add 12 hours if PM bit is set time.hour = Rtc_Ds1307::bcdToDecimal( buffer[2] & 31 ); if ((buffer[2] & 32) == 32) time.hour += 12; } else { time.hour = Rtc_Ds1307::bcdToDecimal( buffer[2] & 63 ); } time.wday = buffer[3]; time.date = Rtc_Ds1307::bcdToDecimal( buffer[4]); time.mon = Rtc_Ds1307::bcdToDecimal( buffer[5]); 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 return true; } bool Rtc_Ds1307::startClock() { char strtStop; INFO ("Reading clock start/stop register value\n"); if (!read(0, &strtStop, 1)) { ERR("Failed to read clock start stop register !\n"); return false; } strtStop &= 0x7F; INFO("Writing back start/stop register value\n"); if (!write(0, &strtStop, 1)) { ERR("Failed to write the start stop register !\n"); return false; } INFO("Start/stop register value successfully written\n"); return true; } bool Rtc_Ds1307::stopClock() { char strtStop; INFO ("Reading clock start/stop register value\n"); if (!read(0, &strtStop, 1)) { ERR("Failed to read clock start stop register !\n"); return false; } strtStop |= 0x80; INFO("Writing back start/stop register value\n"); if (!write(0, &strtStop, 1)) { ERR("Failed to write the start stop register !\n"); return false; } INFO("Start/stop register value successfully written\n"); return true; } bool Rtc_Ds1307::setSquareWaveOutput(bool ena, SqwRateSelect_t rs) { char reg; INFO("Reading register value first\n"); if (!read(7,®, 1)) { ERR("Failed to read register value !\n"); return false; } INFO("[Reg:0x07] = %02x\n", reg); // preserve the OUT control bit while writing the frequency and enable bits reg = (reg & 0x80) | (ena ? 0x10 : 0) | ((char)rs & 0x03); INFO("Writing back register value\n"); INFO("[Reg:0x07] = %02x\n", reg); if (!write(7, ®, 1)) { ERR("Failed to write register value !\n"); return false; } INFO("Successfully changed the square wave output.\n"); return true; } bool Rtc_Ds1307::read(int address, char *buffer, int len) { char buffer2[2] = {(char)address, 0}; // m_rtc->start(); if (m_rtc->write(0xd0, buffer2, 1) != 0) { ERR("Failed to write register address on rtv!\n"); m_rtc->stop(); return false; } if (m_rtc->read(0xd0, buffer, len) != 0) { ERR("Failed to read register !\n"); return false; } m_rtc->stop(); INFO("Successfully read %d registers from RTC\n", len); return true; } bool Rtc_Ds1307::write(int address, char *buffer, int len) { char buffer2[10]; buffer2[0] = address&0xFF; for (int i = 0 ; i < len ; i++) buffer2[i+1] = buffer[i]; // m_rtc->start(); if (m_rtc->write(0xd0, buffer2, len+1) != 0) { ERR("Failed to write data to rtc\n"); m_rtc->stop(); return false; } m_rtc->stop(); return true; } RtcCls::RtcCls(PinName sda, PinName scl, PinName sqw, bool bUseSqw) : Rtc_Ds1307(sda, scl), m_sqw(sqw), m_bUseSqw(bUseSqw), m_bAlarmEnabled(false), m_alarmfunc(NULL) { Time_rtc t; // query time from device getTime(t); // sync the time with MBED RTC struct tm now = {t.sec, t.min, t.hour, t.date, t.mon-1, t.year-1900}; m_time = mktime(&now); set_time(m_time); // Only register the callback and start the SQW if requested to do so. Otherwise the system // will use the MBED built-in RTC. if (m_bUseSqw) { // start the wave setSquareWaveOutput(true, RS1Hz); // register callback from now on the time will be maintained by the square wave input m_sqw.rise(this, &RtcCls::_callback); } } void RtcCls::_callback(void) { // INFO("Tick!"); // Simply increase the number of seconds m_time++; // if (m_bAlarmEnabled && (m_time == m_alarmTime)) { // if (m_alarmfunc != NULL) // m_alarmfunc(); // m_bAlarmEnabled = false; // } } time_t RtcCls::getTime() { // when not using the HW support, we have to query the RTC chip. Other wise we can just return out stored value if (!m_bUseSqw) { Time_rtc t; getTime(t); struct tm now = {t.sec, t.min, t.hour, t.date, t.mon-1, t.year-1900}; m_time = mktime(&now); INFO("getting time %02d.%02d.%04d %02d:%02d:%02d Ticks=%08lx", t.date, t.mon, t.year, t.hour, t.min, t.sec, m_time); } else { INFO("getting time Ticks=%08lx", m_time); } return m_time; } void RtcCls::setTime(time_t t) { Time_rtc tim; struct tm *now; now = localtime(&t); tim.sec = now->tm_sec; tim.min = now->tm_min; tim.hour = now->tm_hour; tim.date = now->tm_mday; tim.mon = now->tm_mon+1; tim.year = now->tm_year + 1900; tim.wday = now->tm_wday +1; setTime( tim, true, true); set_time(t); }