$SL - Sleep mode
This command puts the device into a low-power sleep mode.
$SL [S=<seconds>|U=<[YYYY-MM-DD ]T[hh:mm:ss]>]*xx
Parameter
Description
S=<seconds>
Sleep for this many seconds
U=<[YYYY-MM-DD ]T[hh:mm:ss]>
Sleep until date (optional) and time
Returns one of:
Value
Description
$SL OK*xx
Sleep period accepted, device is now
non-responsive
$SL WAKE,<cause>*xx
Device has woken from selected sleep mode
$SL ERR,GPS_TIMENOTSET*xx
Time not yet set from GPS
$
SL
ERR,<error_type>*xx
Command input error
The
S
parameter is the number of seconds to sleep. This value may range from 5 to 31536000
(approximately 1 year) seconds. If the command is accepted, the device will emit
$SL OK
and
enter sleep mode for the requested duration.
The
U
parameter is a time and optional date the device should sleep until and then wake. If the
date is not specified and the time to sleep until is less than the current time, the time is
presumed to be the next day. For example, if the current time is 11:00:00 and
$SL
U=09:00:00
is issued, the device will wake 22 hours from now. If a date and time are specified,
and that date/time is before the current date/time,
$SL WAKE
will be immediately issued.
The
$SL WAKE,<cause>
message is emitted after the Modem wakes from a user-commanded
sleep mode. The value of
cause
will be one of the following:
Cause
Description
© 2022 SWARM TECHNOLOGIES
SWARM M138 MODEM PRODUCT MANUAL · REV 1.20 · FEBRUARY 2022
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