Omron CJ1W-SCU32 Operation Manual page 291

Error conditions
Serial Indicator
communications display
mode
The serial commu- ---
nications mode is
set to No-protocol
Mode.
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Confirmation of device
variable for CJ-series Unit, etc.
Status and
other
conditions
--- Overrun Error
*_P1(orP2)_OverRunErr is TRUE.
--- The Reception Overflow Flag is
ON.
*_P1(orP2)_NopRcvOvfSta is
TRUE.
--- The Reception Completed Flag is
OFF.
*_P1(orP2)_NopRcvCompleteSta
is FALSE.
--- ---
9 Troubleshooting and Maintenance
Cause
The reception buffer
received more than
259 bytes of data
before the SerialRcv
or SerialRcvNo-
Clear instruction was
executed.
After reception was
completed (after the
Reception Com-
pleted Flag turned
ON), further data
was received (1 byte
or more).
Reception for the
SerialRcv or Serial-
RcvNoClear instruc-
tion was not
completed. One of
the following is the
cause.
The start
code/end code
setting is incor-
rect.
No data was
received.
The specified
number of data
bytes was not
received.
Overrun error
(The reception
buffer received
more than 259
bytes of data
before the Serial-
Rcv or Serial-
RcvNoClear
instruction was
executed.)
A hardware error
occurred in the
reception circuit of
the Unit.
Remedy
Cycle the power or
restart the Unit and
clear the reception
buffer.
The Overrun Error
Flag is turned to
FALSE when the
reception buffer is
cleared.
After data reception
is completed (i.e.,
after the Reception
Completed Flag
changes to TRUE),
execute the Serial-
Rcv or SerialRcvNo-
Clear instruction
again.
---
Revise the settings
for the Start
Code/End Code in
*_P1(orP2)_NopStar
tCodeCfg (No-proto-
col Start Code),
*_P1(orP2)_NopEnd
CodeCfg (No-proto-
col End Code).
Revise the specified
number of receive
data bytes in
*_P1(orP2)_NopRcv
9
DatSzCfg (Number
of Receive Data
Bytes in No-protocol
Mode).
Cycle the power or
restart the Unit to
clear the reception
buffer.
The Overrun Error
Flag is turned to
FALSE when the
reception buffer is
cleared.
Conduct a loopback
test in serial commu-
nications mode to
check the transmis-
sion lines. If an error
occurs during the
test, replace the Unit.
9-13