Mitsubishi MELSEC-A Series Reference Manual page 256

9. PROGRAMMING
Device
Name
Number
M9251 Link halt
M9252 Loop test status
Master station
M9253
operating status
Operating status of
M9254 local stations
except host
Error status of
M9255 local stations
except host
Table 9.3 MELSECNET special link relays list (Continued)
Data
• ON/OFF status depends on whether the station itself stopped the data link.
• Turned ON when the data link is established in neither the forward loop line
OFF : Normal
nor the reverse loop line.
ON : Halt
• Automatically turned OFF when the data link returns to the normal state.
• Only effective while the loop line in which the data link is executed is online.
OFF : Not executed
ON : Forward loop
test or • Turned ON while the host station itself is in the forward loop test mode or
reverse loop the reverse loop test mode.
test is being
executed.
OFF : RUN or
STEP RUN • Controlled according to the operation status of the master station.
status • Turned ON when the status of a master station is either STOP or PAUSE.
ON : STOP or • Turned OFF when the status of the master station changes to RUN or
PAUSE STEP RUN.
status
• Controlled according to the operation status of a local station other than the
host station.
OFF : RUN or
• Turned ON when the status of a local station other than the host station in
STEP RUN
the loop is either STOP or PAUSE.
status
• Not turned ON when the status of the host station itself is either STOP or
ON : STOP or
PAUSE.
PAUSE
• Automatically turned OFF when the status of a local station other than the
status
host station in the loop changes to RUN or STEP RUN. (That is, M9254 is
turned OFF when bits D9248 to D9251 are all OFF.)
• Controlled by detecting an error of a local station other than the host station.
• Turned ON if an error occurs in one local station other than the host station
OFF : Normal in the loop.
ON : Error • Automatically turned OFF when the faulty station returns to the normal state
or the data link returns to the normal state by switching the loop line. (That
is, M9255 is turned OFF when bits D9252 to D9255 are all OFF.)
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Description