Experimental Physics and
Industrial Control System

Maren Purves <[email protected]> · Wed, 24 Jul 2002 08:17:35 -1000

Hi Bernd,

we have such a thing, written by Nick Rees, that in our case runs
at 0 hours UT and makes a date string.

It is a task spawned in the startup file:
taskSpawn ("dhsDailyUpdate", 100, 8, 20000, dhsDailyUpdate)

and the code it runs is as follows:
void dhsDailyUpdate()
{
    time_t    timeNextUpdate = 0;
    time_t    timeNow, timeToday, timeTomorrow;
    struct tm tmNow,   tmToday,   tmTomorrow;
    int secondsDelay;

    do
    {
        /* Find the current time in time_t and struct tm formats */
        timeNow = time(NULL);
        gmtime_r( &timeNow, &tmNow );

        /* Create a tm structure and time_t which is the beginning of
today UTC 
*/
        tmToday = tmNow;
        tmToday.tm_hour = 0;
        tmToday.tm_min  = 0;
        tmToday.tm_sec  = 0;
         timeToday = mktime( &tmToday );

        /* Now create a tm structure and time_t which is the beginning
of tomorr
ow UTC
           Note we rely on the ability of mktime to notice month and
year
           changes to sort these out just from the addition of the day
number */
        tmTomorrow = tmToday;
        tmTomorrow.tm_mday++;
        timeTomorrow = mktime( &tmTomorrow );

        /* Now update the observation number if the next update is
before today
           (the normal occurance) or after tomorrow (indicating that a
time erro
r
           has occurred in the last iteration */
        if (timeNextUpdate <= timeToday || timeNextUpdate > timeTomorrow
)
        {
            DHS_ID pDrv = &dhsDrv;

            dhsObsnum ( pDrv );
            timeNextUpdate = timeTomorrow;
        }

        /* Calculate the number of seconds left in today */
        secondsDelay = 86400 - (tmNow.tm_hour*3600 + tmNow.tm_min*60 +
tmNow.tm_
sec);
        taskDelay( secondsDelay * sysClkRateGet() );
    } while (TRUE);
}

Aloha,

Maren 

Bernd Schoeneburg wrote:
> is there an existing solution or ideas to implement the functionality of
> a switch clock in EPICS? The function, I want is to set one or more
> binary output channels according to the actual time. For example: Output
> 1 should be active every tuesday between 8am and 10am. I think an
> EPICS-record would be a good solution. Is somethink like this existing?

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System