User manual

Section 11: LXI Class B Triggering (IEEE-1588) Series 3700 System Switch/Multimeter Reference Manual
11-8 3700S-901-01 Rev. C / July 2008
Scheduling alarms on a stand-alone Series 3700
To configure a single Series 3700 to perform an event at a particular date and
time, you must schedule alarms, but you do not need to enable IEEE-1588.
Therefore, you can send these commands over any remote interface and not
just LAN.
To initiate a specific action at the firing of the alarm, you must use the event
identifier for the scheduled alarm, schedule.alarm[x].EVENT_ID (on page
13-250), as the stimulus of one of the control sources defined in the trigger
model. Refer to Scanning (on page 7-1) for more details on the trigger model.
The following example demonstrates how to configure a scan of five channels to
run once every hour starting at 3AM on September 1, 2008:
-- convert to UTC time
Start_time = os.time({year=2008, month=9, day=1, hour=3})
-- convert to PTP time
Start_time = Start_time + ptp.utcoffset
-- configure the alarm
schedule.alarm[1].ptpseconds = Start_time
schedule.alarm[1].fractionalseconds = 0
-- configure the alarm repetition count
schedule.alarm[1].repetition = 5
–- set alarm period to 1 hr = 60 secs x 60 mins
schedule.alarm[1].period = 60*60
--enable the alarm
schedule.alarm[1].enable = 1
--associate a DMM configuration and configure a scan
dmm.setconfig("1001:1005", "dcvolts")
scan.create("1001:1005")
-- 5 scans of 5 channels
buf = dmm.makebuffer(25)
-–command the scan to start when alarm 1 fires
scan.trigger.arm.stimulus = schedule.alarm[1].EVENT_ID
--set scan count and initiate execution of background scan
scan.scancount = 5
scan.background(buf)