Mitsubishi MELSEC-A Series Reference Manual page 260

9. PROGRAMMING
Device
Name
Number
D9204 Link status
Table 9.5 List of MELSECNET special link registers (Continued)
Data
0 : Data link in forward loop
1 : Data link in reverse loop
2 : Loopback in forward/
reverse direction
3 : Loopback in forward
direction
4 : Loopback in reverse
direction
5 : Data link impossible
Stores the current path of the data link.
(1) Forward loop
(2) Reverse loop
• Forward/reverse loop
• Forward loopback
• Reverse loopback
• When "5" is stored, the monitering time setting may be too small.
• The data in D9204 is updated each time the link status changes.
• Even if power of the station connected to the bypass switch is
turned OFF, the data link status being executed on the forward or
reverse loop is kept.
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Description