NAME
Device::Chip::PCF8563 - chip driver for a PCF8563
DESCRIPTION
This Device::Chip subclass provides specific communication to a NXP
PCF8563 chip attached to a computer via an I²C adapter.
METHODS
The following methods documented with a trailing call to ->get return
Future instances.
read_time
@tm = $pcf->read_time->get
Returns a 7-element struct tm-compatible list of values by reading the
timekeeping registers, suitable for passing to POSIX::mktime, etc...
Note that the returned list does not contain the yday or is_dst fields.
Because the PCF8563 only stores a 2-digit year number plus a single
century bit, the year is presumed to be in the range 2000-2199.
This method presumes POSIX-compatible semantics for the wday field
stored on the chip; i.e. that 0 is Sunday.
This method performs an atomic reading of all the timekeeping registers
as a single I²C transaction, so is preferrable to invoking multiple
calls to individual read methods.
write_time
$pcf->write_time( @tm )->get
Writes the timekeeping registers from a 7-element struct tm-compatible
list of values. This method ignores the yday and is_dst fields, if
present.
Because the PCF8563 only stores a 2-digit year number and a century
bit, the year must be in the range 2000-2199 (i.e. numerical values of
100 to 299).
This method performs an atomic writing of all the timekeeping registers
as a single I²C transaction, so is preferrable to invoking multiple
calls to individual write methods.
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>