I/o control, Message communications, Fig. 9.5 synchronization with a motion module – Yaskawa MP920 User's Manual Design User Manual

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9.1 Overview

9-7

Fig. 9.5 Synchronization with a Motion Module

I/O Control

For Communications Modules, such as the 215IF and 260IF Modules, that perform I/O
transmission with I/O Modules such as the DI, DO, LIO, CNTR, AI, and AO Modules, spec-
ify the CPU Module that inputs and outputs data using I and O registers as the Control CPU
Module. Change the module output settings of the Sub CPU Module so that the Sub CPU
Module will not output to these Modules. (Refer to 6 Module Configuration Definitions

9.2.2 Setup Procedure Using the MPE720 for details.) Otherwise, outputs from the Sub
CPU Module may conflict with outputs from the Control CPU Module, causing errors such
as undefined output values.

It is possible to read the input data on the Sub CPU Module. However, word data may not be
concurrent because there is no synchronization between inputs from the Sub CPU Module
and inputs from the Motion Module. For example, when reading input data for several words
from an Inverter connected to a network, new and old input data may be mixed. To avoid
this problem and ensure word data concurrency, program the CPU Modules so that the Sub
CPU Module reads the I registers that were read and stored in the shared memory by the
Control CPU Module.

Message Communications

For Communications Modules performing message communications, such as the 217IF,
218IFA, and 215IF Modules, normally specify the CPU Module in which the message func-
tions (MSG-SND and MSG-RCV) are programmed as the Control CPU Module. If the mes-
sage functions are programmed in both CPU Modules, specify CPU Module 1 as the Control
CPU Module.

For Communications Modules, such as the 215IF Module, that perform I/O transmission as
well, however, select the Control CPU Module on the base of the criterion described in I/O
Control, above.

Message processing (MSG-SND and MSG-RCV function processing) is normally executed
in the Sub CPU Module, too, but the transmission parameters in the Control CPU Module
will be used.

CPU Module 1
High-speed
scan

Motion
Module

CPU Module 2
High-speed
scan

I/O

pro-

cessing

I/O

pro-

cessing

I/O

pro-

cessing

I/O

pro-

cessing

I/O

pro-

cessing

I/O

pro-

cessing

Execution of ladder/
motion programs

I/O synchronization

Read

param-

eter

Read

param-

eter

Read

param-

eter

Distri-
bution

Inputs

Outputs

I/O synchronization