Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Wed, 06 Sep 2006 09:31:59 -0500

Tim Mooney wrote:

By the way, you example problem is treated in Ned Arnold's devTimeOfDay.c.
I snuck a copy of this into the synApps std module, if you're interested.

These old timestamp conversion device supports are no longer needed, and
should be eliminated - since R3.14.5 there has been a soft stringin
device support included with Base called devTimestampSI.c whose INST_IO
parm string is a format string for epicsTimeToStrftime() which extends
the strftime() formatting to include fractional seconds.
The time value that this device support converts is the timestamp of the
stringin record itself, but by pointing its .TSEL field to another
record's .TIME field it can be made to convert arbitrary timestamps by
reading them from that other record. If the time you want to convert
isn't in any record's timestamp yet, you can make it one using a
subroutine record whose subroutine sets its own timestamp by converting
it from whatever format you do have (the sub record will need to have
its .TSE field set to -2 to stop it from being overwritten by the record
support afterwards).
Here are a couple of examples, untested.
# timeString gives the timestamp from timeMe
record(bi, "timeMe") {
  field(SCAN, "I/O Intr")
  field(FLNK, "timeString")
  ...
}
record(stringin, "timeString") {
  field(TSEL, "timeMe.TIME")
  field(DTYP, "Soft Timestamp")
  field(INP, "@%Y-%m-%d %H:%M:%S.%9f")
}

# Offset timestamp
record(sub, "drWho") {
  field(TSE, "-2")
  field(SNAM, "timeTravel")
  field(INPA, "10")
}
record(stringin, "timeString") {
  field(TSEL, "delayedTime.TIME")
  field(DTYP, "Soft Timestamp")
  field(INP, "@%Y-%m-%d %H:%M:%S.%9f")
}
static long timeTravel(subRecord *precord)
{
    epicsTimeGetCurrent(&precord->time);
    epicsTimeAddSeconds(&precord->time, precord->a)
    return 0;
}

If somebody wants to test the above and post any corrections this
message can act as an example to future questioners on the topic.
- Andrew
--
There is considerable overlap between the intelligence of the smartest
bears and the dumbest tourists -- Yosemite National Park Ranger

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System