Siemens CPU 948, Programming Manual

Page: 285 / 548

Points to note with the time
parameters Regardless of when a clock-controlled interrupt (timed job) is to be
triggered, the individual time parameters must be specified in certain
combinations. Depending on the selected time for the clock-controlled
interrupt, certain parameters must be specified, while others are not
evaluated by the system program.
The following table shows which time parameters must be specified
for which timed job (XXX = must be specified, --- = irrelevant).
Interval Seconds Minu-
tes
Hours Week-
day
Day of
month Month Year
every minute
every hour
every day
every week
every month
every year
once XXX
XXX
XXX
XXX
XXX
XXX
XXX ---
XXX
XXX
XXX
XXX
XXX
XXX
---
---
XXX
XXX
XXX
XXX
XXX
---
---
---
XXX
---
---
---
---
---
---
---
XXX
XXX
XXX
---
---
---
---
---
XXX
XXX
---
---
---
---
---
---
XXX
When reading out the time parameters, the irrelevant parameters are
assigned the value FFH.
Special situations
••
If the "29th of February" is selected with the job type "every year"
(= 6), this means that OB 9 is only called every leap year.
••
If the value "29", "30" or "31" is selected with the job type "every
month" (= 5), OB 9 is only called in the months which have these
dates.
Table 6-14 Assignment of "timed job - time parameters"
OB 151: Set/Read Time for Clock-Controlled Interrupt
CPU 948 Programming Guide
C79000-G8576-C848-04
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