Mitsubishi Electric MELSEC iQ-R Series User Manual page 444

Displayed items
■Buffer memory area for the display contents
Buffer memory address
■SD WAIT
SD WAIT indicates "Transmission wait status".
Value Status
0001 (ON) Waiting for data transmission
0000 (OFF) Data transmission available
■SIO
SIO indicates "SIO error status".
Value Status
0001 (ON) Overrun or framing error occurred
OS area is full.
0000 (OFF) Normal
■PRO.
PRO. indicates "Character error status".
Value Status
0001(ON) Error occurred
0000(OFF) Normal
■P/S
P/S indicates "Status of parity error or sum check error".
Value Status
0001(ON) Error occurred
0000(OFF) Normal
27 TROUBLESHOOTING
442
27.1 Checking Module Status
to
b15
Un\G513
Un\G514
For system
b8 b7 b6 b5 b4 b3
1/0 1/0 1/0 1/0 1/0
1/0 1/0 1/0 1/0
1/0
1: LED ON, error
0: LED OFF, no error
Description
C24 got into a state in which data cannot be sent to a target device (waiting for data
transmission) by the transmission control of C24.
• The transmission cannot be started.
• A transmission terminate request (receiving DC3/DR(DSR) signal OFF) is received from
the target device during data transmission.
The transmission became available, and the data transmission is started/resumed.
Description
Overrun or framing error occurred.
Keeps the ON-status even after the communication returns to normal. Initialize the error
information as necessary.
Page 473 Error Code List
No free space is available in the OS area, and the received data was discarded.
Keeps the ON-status even after the communication returns to normal. Initialize the error
information as necessary.
Page 473 Error Code List

Description
Character error occurred.
Keeps the ON-status even after the communication returns to normal. Initialize the error
information as necessary.
Page 473 Error Code List

Description
Parity error or sum check error occurred.
Keeps the ON-status even after the communication returns to normal. Initialize the error
information as necessary.
Page 473 Error Code List

b2 b1 b0
1/0 1/0
1/0 (Information on the CH1 side)
1/0
1/0
1/0 (Information on the CH2 side)
SD WAIT
SIO
PRO.
P/S
C/N
NAK
ACK.
NEU.