Mitsubishi Electric MELSEC Q Series User Manual page 242

(b) Manual cyclic data refresh
1) Use the QBF_RefreshLinkDevice function to issue a refresh request.
2) The user program is continued.
3) Data are refreshed by the request in 1).
4) Execute the QBF_FromBuf function with "manual" specified for "CC-Link refresh method" of the third
argument (ulOffset).
Cyclic data (in the buffer memory) are read out.
C Controller module
1)
2)
3)
4)
4)
*1: Read out data are the same refresh data.
• If execution of the QBF_FromBuf function is attempted before refreshing data by the
QBF_RefreshLinkDevice function, user program processing is suspended until completion of the refresh.
Upon completion of the refresh, cyclic data (in the buffer memory) are read out, and the user program
processing resumes.
C Controller module
1)
2)
4)
3)
When any of the following operations is performed for the CC-Link module for which the block data assurance per station
is enabled, cyclic data are automatically refreshed even if the QBF_RefleshLinkDevice function is not executed.
• Monitoring on Setting/monitoring tools for the C Controller module.
• Device reading from another user program (another task) with the QBF_FromBuf function (automatic refresh
method) or a MELSEC data link function
Note that the write (send) area of the link refresh device (in the buffer memory) is not refreshed.
Also, cyclic data are not refreshed when monitoring is performed with another station's CC-Link module specified in
Setting/monitoring tools for the C Controller module.
240
User
program
QBF_RefreshLinkDevice
QBF_FromBuf (manual)
Data read-out
QBF_FromBuf (manual)
Data read-out
User
program
QBF_RefreshLinkDevice
QBF_FromBuf (manual)
Data read-out
: User program is waiting
CC-Link module
Buffer memory
Refresh request
Refresh
*1
*1
CC-Link module
Buffer memory
Refresh request
Refresh
Link scan
Link scan
Link scan
Link scan
Link scan
Link scan