Omron SYSDRIVE 3G3RV, User Manual

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Communications Functions
6-
103
Sequence
number. The sequence number is automatically set.
Communication Sequence
The
label (name) of the sequence. Input an appropriate, easy-to-distinguish name.
Link Word
Set
the area for sharing the data between the Programmable Controller and Communications Board.
In
this example, the link word is specified by the operand of the PMCR instruction. Therefore no link word is
set
here.
Control
Set
the control method, such as flow control.
Select
only “modem control” for communications with the 3G3RV.
Response
A
method to write reception data to the I/O memory of the Programmable Controller.
Select
“notify by scan” for communications with the 3G3RV.
Timer Tr, Timer Tfr, and Timer Tfs
Set
the periods to monitor the transmission and reception steps with timers Tr, Tfr, and Tfs. The following tim-
ing
chart shows the meaning of each monitor.
Be
sure to set the periods according to the application.
The
step will be retried if the step is not completed within the monitor periods. An error will occur if the step
is
not completed within the monitor time again.
Set
a period of approximately 0.5 s each for communications with the 3G3RV.
Fig 6.67
Communication
sequence
Link word Control Response
Timer
Tr
Timer
Tfr
Timer
Tfs
Inverter
I/O Send &
Recv
Set
(Setting required)
Scan 0.5 0.5 0.5
Monitored for
Tfr period
Send & Recv Send
Recv
Ts
Monitored for
Tfs period
Ts: Send wait time set per step. Nothing is sent during this period.
Tfs: Monitors the completion of the data sent. If the data transmission is not finished within this period,
the data will be re-transmitted.
Tr: Monitors the response to be received. If the response is not returned within this period, the response will
be re-transmitted.
Tfr: Monitors the reception completion of the response. If the response transmission is not finished within this
period, the response will be re-transmitted.
Note If the Tr period is too long, the time to detect a communications error will be longer, during which the Inverter
cannot be controlled. Therefore, be sure to set an appropriate period.
Monitored for
Tr period