Mitsubishi MELSEC-A Series Reference Manual page 257

9. PROGRAMMING
Device
Name
Number
LRDP instruction
M9204
completed
LWTP instruction
M9205
completed
Link card error
M9211
(local station)
M9240 Link status
M9246 Data unreceived
M9247 Data unreceived
Parameter
M9250
unreceived
M9251 Link halt
Master station
M9253
operating status
Operating status of
M9254 local stations
except host
Error status of local
M9255 stations except
host
Table 9.4 MELSECNET/B special link relays list
Data
OFF : Uncompleted • Turned ON by a local station upon the completion of word device read
ON : Completed processing called by an LRDP instruction.
OFF : Uncompleted • Turned ON by a local station upon the completion of word device write
ON : Completed processing called by an LWTP instruction.
OFF : Normal
• Turned ON when the link card hardware is faulty.
ON : Error
OFF : Online
ON : Offline, • Turned ON when the host station is in offline, station-to-station test, or self-
station-to- loopback test mode.
station test, • Turned OFF when the host station is reset after being placed in the online
or self- mode.
loopback test
OFF : Received
• Turned ON when the data from the master station has not been received.
ON : Unreceived
OFF : Received • Turned ON when a sub-slave station has not received data from the master
ON : Unreceived station in the three-tire system. (That is, M9247 is ON while M9208 is ON.)
• Turned ON when the link parameters have not been received from the
OFF : Received master station.
ON : Unreceived • Automatically turned OFF when the link parameter is received.
• Only valid while the loop line in which the data link is executed is online.
• Controlled by whether the host station stopped the data link or not.
OFF : Normal
• Automatically turned OFF when the data link returns to the normal status.
ON : Halt
• Only effective while the loop line in which the data link is executed is online.
OFF : RUN or
STEP RUN • Controlled according to the operation status of a master station.
status • Turned ON when the status of the 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 even if the status of the host station 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 and D9249 are OFF.)
• Controlled by detectingby 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 D9253 are all OFF.)
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Description