Omron 3G8F7-CRM21, User Manual

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59
Communications Cycle Control Procedures
Section 5-2
These functions are used during the communications cycle operation.
Function Description
Communications
Cycle Control It is used to control start and stop of communications cycles.
Access to I/O Data Through asynchronous access it merely reads or writes the I/
O data area in the shared memory.
Through synchronous access it uses an interrupt, controls the
access rights and reads or writes the I/O data area.
Access to Status When it accesses to the Basic status group, it merely reads or
writes the basic status area in the shared memory. To obtain
the basic status synchronous with the I/O data, the access
right is controlled at the same time when the I/O data area is
accessed.
When it accesses to the Detailed status group, it uses the
command Request to Read the Detailed Status Group to read
it.
Access to Event
Area It is to transmit and receive Explicit messages.
It uses interrupts as access procedure.
Communication stop
_ Initial state
STOP_CYCLE
STOP_CYCLE
STOP_IOCYCLE START_IOCYCLE
Communications
Cycle Operation
(IDLE state)
Communications
Cycle Operation
(RUN state)
Communications
Cycle Operation
(IDLE state)
[for a specified
period of time]
OPEN_SYSTEM/
OPEN_SYSTEMEX