Siemens CP 342-5 Manual page 26

Application and functions
1.6 Compatibility with the previous product
Topic / relates to
11. Deterministic sending / receipt
of data - coordination between
CPU and CP/PROFIBUS
12. Jobs with DP_SEND and
DP_RECV
1)
13. Receive buffer length to short
for AG_RECV
14. Responder functionality of the
DP master (class 1;
DP master (class 2) passes
jobs to DP master (class 1))
Functions:
"DDLM_GET_Master_Diag
•
"
"DDLM_Act_Param"
•
See also the STEP 7 online help on the SIMATIC NET program blocks for PROFIBUS DP.
1)
Note on 8: Consistency in the data acceptance between CP and user program
Depending on the behavior in the user program, you can consider different areas as
consistent data areas on the transfer interface between CP and user program.
● Variant 1: NDR bit is evaluated on the program block interface
You can assume consistency over the entire DP data area used.
● Variant 2: NDR bit is not evaluated on the program block interface
You can assume data consistency in a contiguous, non-overlapping 32-byte area.
("Non-overlapping" means: 32-byte areas must be counted or taken into account from the
start address "0" of the DP data area under consideration.)
26
Response of the device types
CP 342-5 6GK7 342-5DA00-0XE0
CP 342-5 6GK7 342-5DA01-0XE0
In cyclic DP mode, the job confir-
mation on the program block inter-
face includes the confirmation of
the transfer to PROFIBUS.
DP slave mode:
To start job processing, the pro-
gram blocks DP_SEND and
DP_RECV must be activated at
least once.
DP master mode:
To start received data processing,
the program block DP_RECV must
be activated at least once.
If the receive buffer is too small,
data is received until the buffer size
is reached.
The call is acknowledged with error
code 8185 .
H
- supported by DP master as re-
sponder -
New response of the device types
CP 342-5 6GK7 342-5DA02-0XE0
CP 342-5 6GK7 342-5DF00-0XE0
CP 342-5 6GK7 342-5DA03-0XE0
In cyclic DP mode, the processing cycle on
the CPU is separate from the processing
cycle on the CP.
Send data: The confirmation of the job in-
cludes no confirmation of the successful
transfer to PROFIBUS.
Receive data: It is possible that the same
data was received several times.
Depending on the use, it is adequate to acti-
vate program block DP_SEND or DP_RECV
to activate job processing.
In DP master mode, at least of the two pro-
gram blocks must be activated at least once.
If the receive buffer is too small, no data is
received.
The call is acknowledged with error code
80B1 .
H
- DP master without responder functionality -
CP 342-5 / CP 342-5 FO
Manual, 07/2017, C79000-G8976-C146-10