Program Example - Mitsubishi Electric Melsec QJ71LP21 Reference Manual

6 PROGRAMMING

6.1.2 Program example

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Provide interlocks in programs according to the link status of the host and other
stations.
The following example shows an interlock in the communication program that uses the
link status of the host (SB0047, SB0049) and the link status of station number 2
(SW0070 bit 1, SW0074 bit 1).
(Example)
Set the following values for the timer constant K .
Baton pass status
(T0, T2)
Cyclic transmission status
(T1, T3)
Reason: This way the control is not stopped even if the network detects an
instantaneous error due to a faulty cable condition and noise interference.
Also, the multipliers of 6, 2 and 3 are used as examples.
REMARKS
For details of interlocks for special link instructions, refer to Section 7.4.5.
More than (link scan time
More than (link scan time
6) + (target station CPU sequence scan time
2)
3)
MELSEC-Q
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