# Real time clock

    identifier: 0x1a8b1a28
    extends: _sensor
    tags: 8bit
    status: rc

Real time clock to support collecting data with precise time stamps.

## Registers

    ro local_time @ reading {
        year: u16 { preferred_interval=1000 }
        month: u8 { absolute_min=1, absolute_max=12 }
        day_of_month: u8 { absolute_min=0, absolute_max=31 }
        day_of_week: u8 { absolute_min=1, absolute_max=7 }
        hour: u8 { absolute_min=0, absolute_max=23 }
        min: u8 { absolute_min=0, absolute_max=59 }
        sec: u8 { absolute_min=0, absolute_max=60 }
    }

Current time in 24h representation. Default streaming period is 1 second.

-   `day_of_month` is day of the month, starting at `1`
-   `day_of_week` is day of the week, starting at `1` as monday. Leave at 0 if unsupported.

        ro volatile drift?: u16.16 s @ 0x180

Time drift since the last call to the `set_time` command.

    const precision?: u16.16 ppm @ 0x181

Error on the clock, in parts per million of seconds.

    enum Variant: u8 {
        Computer = 1
        Crystal = 2
        Cuckoo = 3
    }
    const variant?: Variant @ variant

The type of physical clock used by the sensor.

## Commands

    command set_time @ 0x80 {
        year: u16
        month: u8 { absolute_min=1, absolute_max=12 }
        day_of_month: u8 { absolute_min=1, absolute_max=31 }
        day_of_week: u8 { absolute_min=1, absolute_max=7 }
        hour: u8 { absolute_min=0, absolute_max=23 }
        min: u8 { absolute_min=0, absolute_max=59 }
        sec: u8 { absolute_min=0, absolute_max=60 }
    }

Sets the current time and resets the error.