Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 104

3 SPECIFICATIONS
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The link refresh is executed by the END processing of the CPU module, but
reading from/writing to the network module is directly performed when an
instruction is executed; thus the transmission delay time can be reduced.
1) Direct access to the sending station
a) When close to step 0
The direct access is faster by a maximum of one scan of a
sequence program when compared with the link refresh.
(Link refresh)
B0
0
Sequence scan
Link scan
(Direct access)
J1\B0
0
Sequence scan
Link scan
b) When close to END
The link refresh and the direct access occur at almost the same
time.
(Link refresh)
0
Sequence scan
Link scan
(Direct access)
0
Sequence scan
Link scan
END 0 END
Same status as the END processing was executed
END 0 END
B0
END 0 END
J1\B0
END 0 END
MELSEC-Q
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