Mitsubishi Electric MELSEC Q Series Reference Manual page 83

(2) When the punctuality assurance setting is enabled
Each of stations performs the specified number of transient transmissions in one link scan to keep the link scan
time constant, and the punctuality of cyclic transmission is ensured.
(a) When the actual number of transient transmissions is less than the specified one
Dummy data are sent to cover the shortfall.
(b) When the actual number of transient transmissions exceeds the specified one
They are divided and transmitted in several link scans.
Control station
No.1
Request
Link scan time
Link scan time is constant since each station sends
a specified number of transient transmissions.
(3) Setting the punctuality assurance and the number of transient
transmissions
Set the punctuality assurance and the number of transient transmissions in "Supplementary Setting" of "Network
Range Assignment" of the control station. (
Enable "Punctuality is guaranteed", and set a value for "Maximum No. of Transients in One Station".
Normal station Normal station
No.2 No.3
Cyclic transmission
Transient transmission
Transient transmission (dummy transmission)
Page 201, Section 6.3.6)
CHAPTER 4 FUNCTIONS
Normal station
No.4
Response
4
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