Toshiba 2000 V Series Manual page 92

Chapter 4 Operating Procedures for the DN611 (Software)
4
70
Request area
S controller
write
Requested
Request flag
register
Request notice
Request
register
Acknow ledgement
flag register
DN611
Figure 4-15 How to Use the Semaphore Area on Requests
(7) Precautions in using the semaphore area
• Since only a pair of request area and acknowledgment area is available, issue the
next request after the DN611 returns the acknowledgement of a request from the
S controller.
• Don't write data (no MWRITE instruction) in the acknowledgement area/acknowl-
edgement flag register. Otherwise, data could be destroyed.(except (6)(g))
• When writing data in the request area using an MWRITE instruction, be careful of
the top address and the size of data to be written. Failing to do so could lead to
the destruction of the data in other areas, possibly causing the DN611 to malfunc-
tion.
Acknowledgement flag
register read
Completion of
request area read
DN611
internal processing
Request area read Acknowledgment area write
model 2000 DeviceNet Module Manual (DN611/DN611A)
Acknowledgement
area read
Completion of
acknowledgement
area read
Responded