Siemens SIMATIC S7-1500 System Manual page 230

Basics of program execution
10.3 Asynchronous instructions
Example: A job of the "Create_DB" instruction is identified by input parameters
LOW_LIMIT, UP_LIMIT, COUNT, ATTRIB and SRCBLK.
The following table shows which input parameters you use to identify which instruction.
Table 10- 2
Instruction
DPSYC_FR
D_ACT_DP
DPNRM_DG
WR_DPARM
WR_REC
RD_REC
CREATE_DB
READ_DBL
WRIT_DBL
RD_DPARA
DP_TOPOL
Status of an asynchronous instruction
An asynchronous instruction shows its status via the block parameters STATUS/RET_VAL and
BUSY. Many asynchronous instructions also use the block parameters DONE and ERROR.
The figure below shows the two asynchronous instructions WRREC and CREATE_DB.
①
②
③
④
⑤
Figure 10-3
228
Asynchronous instructions Call to job assignment
The input parameter REQ starts the job to execute the asynchronous instruction.
The output parameter DONE indicates that the job was completed without error.
The output parameter BUSY indicates whether the job is currently being executed. When BUSY
=1, a resource is allocated for the asynchronous instruction. When BUSY = 0, the resource is
free.
The output parameter ERROR indicates that an error has occurred.
The output parameter STATUS/RET_VAL provides information on the status of the job execution.
The output parameter STATUS/RET_VAL receives the error information after the occurrence of
an error.
Block parameters of asynchronous instructions using the instructions WRREC and
CREATE_DB as examples.
Job is identified by
LADDR, GROUP, MODE
LADDR
LADDR
LADDR, RECNUM
LADDR, RECNUM
LADDR, RECNUM
LOW_LIMIT, UP_LIMIT, COUNT, ATTRIB, SRCBLK
SRCBLK, DSTBLK
SRCBLK, DSTBLK
LADDR, RECNUM
DP_ID
System Manual, 11/2023, A5E46600094-AD
SIMATIC Drive Controller