This is a port of the Adafruit driver and DateTime library for the DS1307 RTC controller
Dependents: espresso-machine-control SAT_OLED Mbedesclava Mbedmaestra ... more
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RTCLib¶
This was ported from Adafruit's RTCLib
Example¶
#include "mbed.h" #include "DS1307.h" class I2C2 : public I2C { public: I2C2 ( PinName sda, PinName scl, int hz, const char *name = NULL) : I2C ( sda, scl, name) { frequency(hz * 100); }; }; I2C2 gI2c ( p28, p27, 100 ); RtsDs1307 gRtc ( gI2c ); Serial gSerial(USBTX, USBRX); void printDT(char *pre, DateTime &dt) { gSerial.printf("%s - %u/%u/%02u %2u:%02u:%02u\r\n" ,pre ,dt.month(),dt.day(),dt.year() ,dt.hour(),dt.minute(),dt.second() ); } bool rtcUpdate(RtcDs1307 &rtc, int32_t bias) // this must be signed { bool bUpdated = false; // Use the compiled date/time as a basis for setting the clock. // We assign it to a signed integer so that negative biases work correctly int64_t compiledTime = DateTime(__DATE__,__TIME__).unixtime(); // This assumes that the program is run VERY soon after the initial compile. time_t localt = DateTime(compiledTime + bias).unixtime(); // offset by bias // If the stored static time stamp does not equal the compiled time stamp, // then we need to update the RTC clock and the stored time stamp if(*((time_t *)&rtc[0]) != localt) { // Update the RTC time as local time, not GMT/UTC rtc.adjust(localt); // Store the new compiled time statically in the object ram image *((time_t *)&rtc[0]) = localt; // Push the object ram image to the RTC ram image bUpdated = rtc.commit(); } return bUpdated; } int main() { time_t tick = 0; if(rtcUpdate(gRtc, -(5*60*60) )) // CDT gSerial.printf("Updated RTC to compiled time\r\n"); gSerial.printf("compiled %s %s\r\n",__DATE__,__TIME__); DateTime timeFlashed(*((time_t *)&gRtc[0])); printDT("last flashed on",timeFlashed); DateTime dt = gRtc.now(); printDT("reset",dt); gSerial.printf("rtc clock is %s\r\n", (gRtc.isRunning() ? "running" : "halted"); while(1) { if(time(NULL) >= tick) { DateTime dt = gRrtc.now(); gSerial.printf("%u/%u/%02u %2u:%02u:%02u \r" ,dt.month(),dt.day(),dt.year() ,dt.hour(),dt.minute(),dt.second() ); tick = time(NULL)+1; } } }