Mitsubishi Electric MELSEC Q Series User Manual page 241

(4) Reading from buffer memory when using the block data assurance per station
function
To enable the Block Data Assurance per Station and read data from the buffer memory, follow the following
procedures.
Method
Automatic cyclic data
refresh
Manual cyclic data
refresh
Use the manual cyclic data refresh method if user program processing is to be continued during the waiting time which will
occur in the automatic cyclic data refresh.
● The following shows the CC-Link module that supports the block data assurance per station function.
Model
QJ61BT11N
(a) Automatic cyclic data refresh
1) Execute the QBF_FromBuf function with "automatic" specified for "CC-Link refresh method" of the third
argument (ulOffset).
2) In the timing of the next link scan, refreshed cyclic data (in the buffer memory) are read out.
User program processing is suspended until the reading is completed.
3) Upon completion of reading, the user program processing resumes.
C Controller module
User
program
1)
QBF_FromBuf (automatic)
2)
3)
: User program is waiting
During execution of the QBF_FromBuf function, a time of up to one link scan may be spent for standby.
CHAPTER 13 FUNCTIONS ACCESSED VIA A NETWORK MODULE
Description
Data are automatically refreshed during the link scan and read out
just by executing the QBF_FromBuf function.
Data are manually refreshed with the QBF_RefreshLinkDevice
function, and then they are read out by executing the QBF_FromBuf
function.
Serial number whose first five digits are "08032" or higher.
Buffer memory
Data read-out
Version
CC-Link module
Link scan
Refresh request Link scan
Refresh
Reference
Page 239, (4)(a) in this
section
Page 240, (4)(b) in this
section
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239