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332
Troubleshooting
Section 11-3
The serial com-
munications
mode is set to no-
protocol mode.
The SD
@
/
RD
@
and
COM
@
indi-
cators do not
flash at all.
(Communica-
tions have not
been electri-
cally estab-
lished.)
---
---
A hardware error
has occurred.
Conduct a loopback
test in serial com-
munications mode
to check the trans-
mission lines. If an
error occurs during
the test, replace the
Board or Unit.
---
---
The cables are
not connected
correctly.
The setting of the
2/4-wire switch
for the RS-422A/
485 port does not
match the actual
wiring.
The wiring of
adapters such as
the NT-AL001-E
is incorrect.
Check the wiring.
Reset the port to
the correct wiring
setting.
Wire all nodes
using the 4-wire
method.
---
CTS control is ON, but bit 04
of word n+7/n+17 (CS) is
OFF.
CTS control is
set, but the
remote node’s
RS signal is not
being input in the
local node’s CS
signal.
Perform either of
the following:
Loop the RS-CS
signals of the local
node.
Disable CTS con-
trol.
Input the RS signal
from the remote
node to the CS sig-
nal of the local
node and use CTS
control.
The SD
@
and
COM
@
indi-
cators flash
but communi-
cations are
not always
possible.
A transmis-
sion error has
occurred.
CIO word n+8/n+18 bit 15
(transmission error) or bit 04
(overrun error) is ON.
The settings in
the Setup Area
such as baud
rate and frame
format do not
match those of
the remote
device. The baud
rate is outside
the permissible
range, or the bits
have been dis-
placed due to a
stop bit error or
other error.
Correct the set-
tings in the Setup
Area.
Revise the remote
device settings and
program (e.g., baud
rate, frame format)
Error conditions
Words allocated in CIO
Area
Cause
Remedy
Serial communi-
cations mode
Indicator
display
Status and
other condi-
tions
Summary of Contents for SYSMAC CJ1W-SCU21-V1
Page 3: ...iv...
Page 5: ...vi...
Page 9: ...x...
Page 15: ...xvi...
Page 89: ...60 Basic Operating Procedure Section 1 9...
Page 151: ...122 RS 232C and RS 422A 485 Wiring Section 3 4...
Page 173: ...144 Host Link Function for Replacing Existing PLCs Section 4 6...
Page 223: ...194 Enhanced Protocol Macro Functions Section 5 6...
Page 277: ...248 Communications Frames Section 6 8...
Page 291: ...262 Basic Operating Procedure in No protocol Mode Section 7 4...
Page 301: ...272 Auxiliary Area and CIO Area Allocations Section 8 3...
Page 391: ...362 Introduction Appendix A...
Page 421: ...392 CompoWay F Master Protocol Appendix B...
Page 513: ...484 E5 K Digital Controller Read Protocol Appendix F...
Page 571: ...542 E5ZE Temperature Controller Write Protocol Appendix I...
Page 587: ...558 E5 J Temperature Controller Protocol Appendix J...
Page 627: ...598 ES100 Digital Controller Protocol Appendix K...
Page 661: ...632 V500 V520 Bar Code Reader Protocol Appendix M...
Page 697: ...668 3Z4L Laser Micrometer Protocol Appendix N...
Page 717: ...688 Visual Inspection System Protocol Appendix O...
Page 755: ...726 V600 V620 ID Controller Protocol Appendix P...
Page 763: ...734 Hayes Modem AT Command Protocol Appendix Q...
Page 767: ...738 Changing Communications Port Settings Using STUP 237 Appendix R...
Page 781: ...752 Revision History...