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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
Содержание 3G8F7-CRM21
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Страница 30: ...10 Specifications Section 1 7 1 7 3 Dimensions 3G8F7 CRM21 PCI unit mm 3G8F8 CRM21 CompactPCI unit mm...
Страница 46: ...26 Connecting the Communications Power Supply Cables Section 2 4...
Страница 74: ...54 Board Hardware Error Notification Section 4 8...
Страница 173: ...153 APPENDIX D Sample Program D 1 Sample Program 154...
Страница 230: ...210 Wiring for Power Supply Section E 5...
Страница 234: ...214 Index...
Страница 236: ...216 Revision History...
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