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61
Communications Cycle Control Procedures
Section 5-2
5-2-3
Control of I/O Data Access
[Asynchronous access]
Constant reads and writes to and from the I/O Data Group (0x0100) are
supported in the normal communications cycles.
[Synchronous access]
Follow these steps in order to use synchronous access:
.
5-2-4
Control of Status Access
[Access to Basic Status Group]
Constant reads and writes to and from the Basic Status Group (0x0042) are
supported in the normal communications cycles.
[Access to Detailed Status Group]
Follow these steps in order to read the Detailed Status Group:
.
Step
Operation procedure
Access to Shared Memory
1.
Notify an access right
request.
Set the REQ_ACC flag in the Interrupt Trigger register
(0x0002) to 1.
2.
Confirm the REQ_ACC
completes the process for
this Board.
Confirm, by polling, the REQ_ACC flag in the Interrupt
Request Confirmation register (0x0003) changes to 0.
3.
Wait for getting an access
right.(This is the case
when the
REQ_ACC_ACK is
confirmed by polling.)
Wait for the REQ_ACC_ACK Interrupt Cause in the
Interrupt Cause Indication register (0x0005) to be 1
periodically.
4.
Clear the Interrupt cause
after confirming it.
Set the REQ_ACC_ACK flag of the Interrupt Clear
register (0x0006) to 1 and clear the interrupt cause.
5.
Read and write I/O data.
Read and write I/O data from and to the I/O Data Group
(0x0100).
6.
Notify a release of the
access right.
Set the REQ_REF flag in the Interrupt Trigger register
(0x0002) to 1.
7.
Confirm the REQ_REF
completes the process for
this Board.
Confirm the REQ_REF flag in the Interrupt Request
Confirmation register (0x0003) turns to 0.
Step
Operation procedure
Access to Shared Memory
1.
Set the command
REQUEST_STATUS.
Select the status to read into the CompoNet Master
Board as the argument of Command area (PC
→
BD)
(0x3200). Set the command REQUEST_STATUS.
2.
Notify the command is
set.
Set the CMD flag of the Interrupt Trigger register (0x0002)
to 1.
3.
Confirm the command
set has been notified.
Confirm the CMD flag of the Interrupt Request
Confirmation register (0x0003) changes to 0.
4.
Wait for a command
acknowledgment.
Confirm the CMD_ACK flag of the Interrupt Request
Indication register (0x0005) changes to 1. (Check it by an
interrupt or polling.)
Содержание 3G8F7-CRM21
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Страница 10: ...x TABLE OF CONTENTS...
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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