NAME
Device::Chip::DS1307
- chip driver for a DS1307
DESCRIPTION
This Device::Chip subclass provides specific communication to a Maxim Integrated DS1307 chip attached to a computer via an I²C adapter.
METHODS
The following methods documented in an await
expression return Future instances.
read_FIELD
$sec = await $ds->read_seconds;
$min = await $ds->read_minutes;
$hr = await $ds->read_hours;
$wday = await $ds->read_wday;
$mday = await $ds->read_mday;
$mon = await $ds->read_month;
$year = await $ds->read_year;
Reads a timekeeping field and returns a decimal integer. The following fields are recognised:
The hours
field is always returned in 24-hour mode, even if the chip is in 12-hour ("AM/PM") mode.
write_FIELD
await $ds->write_seconds( $sec );
await $ds->write_minutes( $min );
await $ds->write_hours ( $hr );
await $ds->write_wday ( $wday );
await $ds->write_mday ( $mday );
await $ds->write_month ( $mon );
await $ds->write_year ( $year );
Writes a timekeeping field as a decimal integer. The following fields are recognised:
The hours
field is always written back in 24-hour mode.
read_time
@tm = await $ds->read_time;
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 DS1307 only stores a 2-digit year number, the year is presumed to be in the range 2000
-2099
.
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
await $ds->write_time( @tm );
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 DS1307 only stores a 2-digit year number, the year must be in the range 2000
-2099
(i.e. numerical values of 100
to 199
).
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>