Siemens Simantic Net NCM for Industrial Ethernet S7 - Manual (Page 163)

Programming FCs (Functions) and FBs for S7 Ethernet CPs
163
SIMATIC NET NCM S7 for Industrial Ethernet
C79000-G8976-C129–06
How the Block Works
The following diagram illustrates the normal sequence of data acceptance
triggered by an AG_RECV in the user program.
Each AG_RECV job in the user program is acknowledged by the Ethernet CP with
an entry in the output parameters NDR, ERROR and STATUS.
Accept / evaluate
received data “A”
User program
(CPU cycle) Ethernet CP Communications Partner
1, 0, 0000 1)
0, 1, 8180 1)
AG_RECV
AG_RECV
AG_RECV
0, 0, 8180 1)
1, 0, 0000 1)
AG_RECV
AG_RECV
Transfer
“A”
active on
Ethernet
Transfer
“B”
active on
Ethernet
Transfer
“C”
active on
Ethernet
Legend:
1) Parameter transfer NDR, ERROR, STATUS
Time Time Time
Accept / evaluate
received data “B”
.
.
.
The status code is updated at each block call.