Omron SYSMAC CJ1W-SCU21-V1, Руководство по эксплуатации

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Using Protocol Macros Section 5-4
whole area if the number of words is specified as 00), then the initial value
will be set to 0000 Hex.
3. The data that has been received as the result of executing the RECV com-
mand will be stored in the reception buffer (except for the first word) from
the specified first word (offset) and will be verified against the expected re-
ceive messages. If writing the response data is not specified, the receive
data will be saved in the reception buffer and will not be stored in the CPU
Unit.
4. If writing the response data is specified, the data in the reception buffer up
to the most recent data (except for the first word), will be stored in from
words R+1 onwards. The data stored for the number of words (including R)
up to the last word will be saved. Whenever the number of data words
stored exceeds the maximum, the number of words in R will be updated.
5. Steps 3 and 4 are repeated until the protocol macro operation is complet-
ed.
Note Processing When a Sequence Ends Abnormally
As shown in the following examples, if END is set when a sequence ends nor-
mally and ABORT is set when a sequence ends abnormally, it is possible to
determine whether each sequence has ended normally or abnormally by
using the Sequence End Completion Flag and the Sequence Abort Comple-
tion Flag.
Reception buffer
Overwrites
initial value
I/O memory
No. of words
specified here I/O memory
Set
CPU Unit
Serial Communications
Board or Unit
Reception
buffer
After PMCR(260)
instruction is executed
the internal
processing buffer is
cleared
Stores
receive data
Write response specified
Stored from the
specified first word
Offset
Receive data
Overwrites receive data
RECV
Changed
No. of words is stored
and updated.