This library is intended to make use of the MCP7940N RTC under the Arduino environment for the ESP8266, ESP01, ESP12E & all other derivative hardware.
It's been based on the DS1307RTC library and its main purpose is to be used in conjuction with the Time library.
First of all object should be created by passing the SDA & SCL pin numbers to its contructor:
const uint8_t SCLPIN = 12;
const uint8_t SDAPIN = 14;
MCP7940NRTC RTC = MCP7940NRTC(SDAPIN, SCLPIN);Once the object has been created you can now invoke its methods normally. They are as follows:
//Acquire data from hardware and return time_t
//Returns 0 if there is a comms issue or oscillator is halted
time_t get();
//Sets the HW clock to the time given in time_t format
//Returns false if there was a communication error
bool set(time_t t);
//Returns the HW time in tmElements_t format
//False if theres a comms issue or oscillator is halted
bool read(tmElements_t &tm);
//Writes the given data to the HW registers
//Returns false if there was a comms error
bool write(tmElements_t &tm);
//This is set to true when no communication errors exist
bool chipPresent();
//Checks the oscillator running bit
bool isRunning();
//Checks the external battery status
bool getBatteryStatus() const;
//Sets the external battery
void enableBattery();
void disableBattery();Please see attached examples folder to get an idea of it's basic usage.
- Calibration procedure
- Retrieving of power down/up status bit and timestamps
- Alarm functionality
- Internal SRAM