Transmission delays, 6-6 transmission delays, Send(090) – Omron CS1W-ETN21 User Manual

Page 172

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147

Communicating between OMRON PLCs

Section 6-6

6-6-6

Transmission Delays

The methods of computing the maximum time required from execution of the
SEND(090), RECV(098), and CMND(490) instructions until processing is
completed are described in this section.

SEND(090)

The transmission delay for the SEND(090) instruction can be calculated using
the following equation, which is illustrated in the following diagram.

CPU Bus Unit Service Cycle (Local Node)

The processing time will be as follows, depending on the CPU processing
mode settings at the CPU Unit:

For details, refer to the CPU Unit operation manual.

Max. delay =

CPU Bus Unit service cycle (local node)

+CPU Bus Unit service processing time (local node)

+Transmission processing time

+Transmission Delays

+Reception processing time

+CPU Bus Unit service cycle (remote node)

+CPU Bus Unit service processing time (remote node)

Maximum transmission delay

CPU Bus Unit
service cycle (local node)

CPU Bus Unit service
processing time (local node)

CPU Bus Unit
service cycle (remote node)

CPU Bus Unit service
processing time (remote node)

Transmission processing time

Reception processing time

Transmission Delays

CPU data set
processing time (remote node)

SEND(090) executed
in user program

CPU execution mode

Processing time considerations

Normal Mode

CPU Unit cycle time

Priority peripheral ser-
vicing

Parallel processing with
synchronous memory
access

Parallel processing with
asynchronous memory
access

0.2 ms + peripheral servicing time (1 ms max. of peripheral
servicing time for each Special I/O Unit, CPU Bus Unit,
peripheral port, RS-232C port, and Inner Board)

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