Siemens SIMATIC S5 Manual page 19

2 Engineering
This process will be repeated by the SIMATIC S5 actively and cyclically every
second.
After having restarted the S7-1500 or the SIMATIC S5-CPU, the count values are
reset via a generated deletion identifier.
Description of the blocks
Table 2-6
Block
OB 100
OB 1
FC 40
DB 113
DB 114
OB 100 (startup OB)
After having restarted the S7-1500 CPU, a deletion identifier ("A1A1") is entered
into the FETCH data area ComFetchDB (DB113). It has the effect that the count
values are reset.
OB 1 (cyclic OB)
The OB1 calls the FC 40 that manages the data management of the passive
FETCH and WRITE functions.
FC 40 (FWDataManagement)
The data area of the WRITE DB called ComWriteDB (DB114) is checked cyclically.
To visualize the ongoing communication, the count value (WRITE function) written
by the SIMATIC S5 is copied to an output area (AB 0) of the S7-1500.
The count value received by the SIMATIC S5 is in the first data word (DW1) of the
WRITE data block ComWriteDB, is incremented by +1 and copied to the FETCH
data area ComFetchDB. These data now are requested by the SIMATIC S5 via the
FETCH connection.
In addition, the written data are checked.
The data are cyclically checked for a deletion identifier ("A1A1") being
-
available. In case of a match, the count value is reset.
If a data identifier ("1234") is detected, the received count value will be
-
incremented by +1 and copied to the FETCH data area.
- The ongoing communication of the FETCH and WRITE services can be seen
from the output area of the S7-1500.
Ethernet Communication (ISO on TCP) between SIMATIC S5 and
SIMATIC S7-1500 Controllers
Entry-ID: 109482475, V1.2,
Symbol
Startup
Main
FWDataManagement
ComFetchDB
ComWriteDB
07/2019
Description
Startup OB
Cyclic OB
Management of the FETCH/WRITE data
management, data verification
Data area for read access from the SIMATIC
S5
Data area for write access from the
SIMATIC S5
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