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4.3 CC-Link Module Access Function
4.3.1 Block guarantee of cyclic data per station
4
FUNCTIONS
• If a value is written to the same address area before execution of the
QBF_RefreshLinkDevice function, the area is overwritten with the value
written later.
By writing the value to another address area, both of the data can be
written.
• If data writing is attempted before completion of the refresh after execution
of the QBF_RefreshLinkDevice function, the data will not be written until
completion of the previous refresh.
Figure 4.9 Write operation
Figure 4.10 Write operation
Buffer memory
Link scan
C Controller module CC-Link module
Refresh
(Data 1) + 2))*1
Link scan
Refresh request
QBF_RefreshLinkDevice function
QBF_ToBuf function (Manual) 1)
QBF_ToBuf function (Manual) 2)
*1 Since writing these data to the same address overwrites the area in the buffer memory,
newly written data are refreshed.
If written to different addresses, both data are refreshed.
User program
Buffer memory
Link scan
C Controller module CC-Link module
Link scan
QBF_ToBuf function (Manual) 1)
:User program is in standby state.
Link scan
Refresh request
Refresh
(Data 1))
Refresh
(Data 2))
QBF_RefreshLinkDevice function
QBF_RefreshLinkDevice function
QBF_ToBuf function (Manual) 2)
Refresh request
User program