Technical data

Table Of Contents
Organization Blocks
System Software for S7-300/400 System and Standard Functions - Volume 1/2
A5E00709327-01
1-21
1.11 Synchronous Cycle Interrupt OBs (OB 61 to OB 64)
Description
Synchronous cycle interrupts give you the option of starting programs in
synchronous cycle with the DP cycle. OB 61 serves as an interface OB to the
synchronous cycle interrupt TSAL1. You can set the priority for OB 61 between 0
(OB deselected) and from 2 to 26.
!
Caution
For direct access with L or T commands (e.g. L PEB, T PAB) as well when using
SFCs 14 "DPRD_DAT" and 15 "DPWR_DAT", avoid accessing I/O areas, whose
process image partitions are assigned with a connection to OB6x (synchronous
cycle interrupt)
Local Data for the Synchronous Cycle Interrupt OBs
The following table describes the temporary (TEMP) variables of the synchronous
cycle interrupt OBs. The variable names are the default names of OB 61.
Variable Data Type Description
OB61_EV_CLASS BYTE Event class and IDs:
B#16#11: Interrupt is active
OB61_STRT_INF BYTE B#16#64: Start request for OB 61
:
B#16#67: Start request for OB 64
OB61_PRIORITY BYTE Assigned Priority class; default: 25
OB61_OB_NUMBR BYTE OB number: 61 … 64
OB61_RESERVED_1 BYTE Reserved
OB61_RESERVED_2 BYTE Reserved
OB61_GC_VIOL BOOL GC violation
OB61_FIRST BOOL First use after startup or stop status
OB61_MISSED_EXEC BYTE Number of failed starts of OB 61 since last execution of
OB 61
OB61_DP_ID BYTE DP master system ID of the synchronous DP master
system
OB61_RESERVED_3 BYTE Reserved
OB61_RESERVED_4 WORD Reserved
OB61_DATE_TIME DATE_AND_TIM
E
DATE_AND_TIME of day at which the OB was called.