Returns true if the current or given time is AM.

// Print true or false depending on whether the current time is AM

// Print whether the given time is AM, in this case: true

Optional parameter: time_t (Unix timestamp), coordinated universal time (UTC)

Returns: Unsigned 8-bit integer: 0 = false, 1 = true

If you have set a timezone using zone(), beginDST(), etc. the hour returned will be local time. You must still pass in UTC time, otherwise the time offset will be applied twice, potentially causing AM/PM to be calculated incorrectly.