Mitsubishi MELSEC-A Series Reference Manual page 251

9. PROGRAMMING
Device
Name
Number
Link parameter
check instruction
M9209 (lower tier link
master stations
only)
Link card error
M9210
(master station)
M9224 Link status
M9225 Forward loop error
M9226 Reverse loop error
M9227 Loop test status
Local station
M9232
operating status
Table 9.1 MELSECNET special link relays list (Continued)
Data
OFF : Check • Turned ON when the link devices (B and W) used by the upper tier and
executed lower tier are not compared for "match".
ON : Check not • When M9209 is OFF, the link parameters for the upper tier and lower tier
executed are checked.
OFF : Normal
• Turned ON when the link card hardware is faulty.
ON : Error
OFF : Offline
ON : Online, • Turned ON when the master station is offline, in the station-to- station test
station-to- mode, or in the self-loopback test mode.
station test, • Turned OFF when the master station is reset after being placed in the
or self- online mode.
loopback test
• Turned ON when any of the following errors occurs on the forward loop line
between the master station and the final station:
• Cable disconnection
OFF : Normal • Forward loop receiver error of the master station link module
ON : Error • Forward loop transmitter error of the link module on the final local station
• Turned ON when the station-to-station test, including the final station, is
executed during the data link.
• Turned OFF automatically when the error state is eliminated.
• Turned ON when any of the following errors occurs on the reverse loop line
between the master station and station No.1 :
• Cable disconnection
OFF : Normal • Reverse loop receiver error of the master station link module
ON : Error • Reverse loop transmitter error of the link module on station No.1
• Turned ON when the station-to-station test was executed at station No.1,
during data link execution.
• Turned OFF automatically when the error state is eliminated.
OFF : Unexecuted
ON : Forward loop
test or • Turned ON when a forward loop test or reverse loop test is being executed
reverse loop for the master station.
test being
executed
OFF : RUN or • ON/OFF status depends on the operation status of the local station.
STEP RUN • Turned ON when the status of any local station in the loop changes to
status STOP or PAUSE.
ON : STOP or • Turned OFF automatically when the status of all local stations changes to
PAUSE RUN or STEP RUN. (That is, M9232 is turned OFF when bits D9212 to
status D9215 are all OFF.)
Description
9 - 5