Mitsubishi MELSEC-Q Series User Manual page 84

4
FUNCTIONS
(4) How to write cyclic data (buffer memory)
Automatic cyclic data
refresh method
Manual cyclic data
refresh method
4
- 11
4.3 CC-Link Module Access Function
4.3.1 Block guarantee of cyclic data per station
Cyclic data can be written to the buffer memory with the functionality of the block
guarantee of cyclic data per station as described below.
If any other method is used, cyclic data per station are not be guaranteed.
1) With the CC-Link utility, make setting to enable the Block guarantee of
cyclic data per station. (
2) Select either of the following.
Table4.5 Writing cyclic data (buffer memory)
Method
Only by executing the QBF_ToBuf function, data are written
and automatically refreshed (at the next link scan).
Data are written in advance with the QBF_ToBuf function, and
then manually refreshed by executing the
QBF_RefreshLinkDevice function.
(a) Automatically refreshing cyclic data
1) Execute the QBF_ToBuf function with "automatic" specified for "The link
refreshing method of the CC-Link link" of the third argument (ulOffset).
2) In the timing of the next link scan, data are refreshed.
C Controller module
User program
1)
QBF_ToBuf function (Auto)
)
2
Section 9.3.5)
Description
Buffer memory
Writing data
Figure 4.6 Write operation
Reference
section
CC-Link module
Link scan
Refresh request
Link scan
Refresh
(a)
(b)