Returns true or false depending on whether the given alarm has been triggered, and resets the alarm flag bit.

Enable or disable an alarm "interrupt" which asserts the INT pin on the RTC.

BCD-to-Decimal conversion

Initialize the I2C bus.

Returns true or false depending on whether the given alarm has been triggered, without resetting the alarm flag bit.

Clears the given alarm flag bit if it is set. Returns the value of the flag bit before if was cleared.

Decimal-to-BCD conversion

Enable or disable the 32kHz output.

Read the current time from the RTC and return it as a time_t value. Returns a zero value if an I2C error occurred (e.g. RTC not present).

Returns the value of the oscillator stop flag (OSF) bit in the control/status register which indicates that the oscillator is or was stopped, and that

Read the current time from the RTC and return it in a tmElements_t structure. Returns the I2C status (zero if successful).

Read multiple bytes from RTC RAM. Valid address range is 0x00 - 0xFF, no checking. Number of bytes (nBytes) must be between 1 and 32 (Wire library lim

Set the RTC to the given time_t value and clear the oscillator stop flag (OSF) in the Control/Status register. Returns the I2C status (zero if success

Set an alarm time. Sets the alarm registers only. To cause the INT pin to be asserted on alarm match, use alarmInterrupt(). This method can set eithe

Enable or disable the square wave output. Use a value from the SQWAVE_FREQS_t enumeration for the parameter.

Returns the temperature in Celsius times four.

Set the RTC time from a tmElements_t structure and clear the oscillator stop flag (OSF) in the Control/Status register. Returns the I2C status (zero i

Write multiple bytes to RTC RAM. Valid address range is 0x00 - 0xFF, no checking. Number of bytes (nBytes) must be between 1 and 31 (Wire library limi