Siemens SIMATIC S5 Manual page 212

S5-115F Manual
Call and Parameter Assignment
Parameter Meaning
SYNC Synchroni-
zation pa-
rameter
You can continue to specify a location parameter in bits 8 to 15 of the synchronization parameter.
Assign an ordinal number in your user program at each FB 254 SYNC call.
In the event of an error message as a result of intervals between FB 254 SYNC calls being too long,
the location parameter of the first wrongly located FB 254 SYNC is output. This makes it easier for
the user to correct errors.
The location parameter is displayed in hexadecimal form. The location parameter 00
specified in the case of error messages when the monitoring facility has detected synchronization
intervals in the monitoring system which are too long.
However, if you want to dispense with assignment of location parameters, set bits 8 to 15 of the
synchronization parameter to "0". Please note that all error messages take the location parameter
"00 " in this case because of excessive call intervals. You receive no indication as to whether the
H
monitoring facility has detected excessive synchronization intervals in the operating system or in
the user program.
Note
Make the intervals between the FB 254 calls 10 ms shorter for a desired interrupt
response time.
Note
FB 254 calls make the scan time longer. Always try to activate as many functions as
possible with as few calls as possible.
EWA 4NEB 811 6149-02
Type Data
Type
D KM Bit 0 = 1 :
Bit 1 = 1 :
Bit 2 = 1 :
Bit 3 = 1 :
All 16 possible combi-
nations are permis-
sible. Both subunits are
synchronized at 0000.
Bits 4 to 7 = 0
Bits 8 to 15: Freely
Assignment
Update of user
times
Synchronize
handling of
interrupt and
time OB 13
Programmer
processing
SINEC L1
processing
programmable
localization pa-
rameters
Blocks
STL
: JU FB 254
Name : AGF:SYNC
SYNC :
is always
H
6-11