Mitsubishi A1SJH - Page 166

APPENDICES
APP - 32
MELSEC-
A
Table 2.2 Special registers list (Continue)
Number Name Description Details Applicable CPU
Mode setting
0 Auto-
matic
online
return
enabled
• When an I/O module or a remote terminal
module caused communication error, the
station is placed offline.
• Communication with normal stations is
continued.
• The station recovering from a
communication error automatically
resumes communication.
1 Auto-
matic
online
return
disabled
• When an I/O module or a remote terminal
module caused communication error, the
station is placed offline.
• Communication with normal stations is
continued.
• Though a faulty station returned to normal,
communication is not restored unless the
station module is restarted.
2 Trans-
mission
stop at
online
error
• When an I/O module or a remote terminal
module caused communication error,
communication with all stations is stopped.
• Though a faulty station returned to normal,
communication is not restored unless the
station module is restarted.
D9173 Mode setting
0: Automatic online
return enabled
1: Automatic online
return disabled
2: Transmission stop
at online error
3: Line check
3Line
check
• Checks hardware and connecting cables
of I/O modules and remote terminal
modules.
—
Usable with A2C
and A52G.
D9174
Setting of the
number of retries
Number of retries
• Sets the number of retries executed to I/O modules and
remote terminal modules which caused communication
error.
• Set for 5 times at power on.
• Set range: 0 to 32
• If communication with an I/O module or a remote
terminal module is not restored to normal after set
number of retries, such module is regarded as a faulty
station.
—
Usable with A2C
and A52G.
D9175
Line error retry
counter
Number of retries
• Stores the number of retries executed at line error (time
out).
• Data becomes 0 when line is restored to normal and
communication with I/O modules and remote terminal
modules is resumed.
—
Usable with A2C
and A52G.