Mitsubishi Electric QJ71C24N User Manual page 341

11 TROUBLESHOOTING
Error code
Error
(Hexa-
decimal)
Modem connection
7E6F
H
error
7E70 CPU error
H
7E73
H
to
7E8E
System error
H
7EC1
H
7EC2
H
Double send
7EC3
H
request error
Transmission data
count error
7EC4 Transmission/
H
receipt buffer setting
error
Flash ROM access
7EC5
H
error
Flash ROM access
7EC6
H
error
7F00 System error
H
7F01 Buffer full error
H
7F02
H
to System error
7F06
H
ASCII BIN
7F20
H
conversion error
Receive header
7F21
H
area error
11 - 25
Description
 Modem is connected to an incorrect
channel.
 The communication with the CPU could
not be performed normally.
 The OS of the Q series C24 detected
some error.
 A send request was performed while
another send request was being
processed.
 Data larger than the transmit buffer size
was transmitted.
 Transmission/receipt buffer settings out
of range.
 Write to Flash ROM was requested
when the setting modification
enable/disable switch in GX Developer
was set to OFF.
 There is an error in the Flash ROM
read/write request contents.
 The OS of the Q series C24 detected
some error.
 The next data was received before
processing of the previous data was
completed.
 Multiple requests was simultaneously
issued for one channel.
 The OS of the Q series C24 detected
some error.
 An ASCII code that cannot be
converted to binary code was received.
 An odd number of bytes of data was
received during data communications
using ASCII BIN conversion.
 When data are received by the protocol
including a packet that contains a
conversion variable, the data
corresponding to the conversion
variable cannot be converted to binary
numbers.
 When data are received by the protocol
including a packet that contains an error
check code (ASCII hexadecimal or
ASCII decimal), the data corresponding
to the error check code cannot be
converted to binary numbers.
 There is an error in the command
(frame) part.
 An ASCII code that cannot be
converted to binary code was received.
Signal
Corrective action
name
 Correct the C
to which notification is
H

sent.
 If there is an error in the CPU, eliminate
C/N the error on the CPU side and
communicate again.

1
 Interlock (handshake) the send

requests.
 Make the transmission data count
smaller than the transmit buffer size.
 Make the non procedure protocol

transmit buffer size larger.
 Designate the first address and size of
transmission/receipt buffer in the free
area range of the user.
 When writing to Flash ROM, set switch

shown left of the given interface to ON
and restart the Q series C24.
 Check the read/write request data and

designate the correct data.

1
 Increase the transmission time by
performing handshake with the external
device, etc.

 Perform handshake with the request
source external device.

1
 Check and correct the external device
transmit message and restart data
communications.
 When data are converted between
ASCII and binary, always transmit data
in units of even bytes.
 Confirm the message sent from the
external device, correct it, and restart
the communication.
 If GX Configurator-SC (Pre-defined
protocol support function) was used for
PRO
protocol editing, check the sender's
packet format to see if an incorrect
value is set for Conversion, Sign
character, Number of decimals,
Delimiter, or number of digits of the
conversion variable.
 If GX Configurator-SC (Pre-defined
protocol support function) was used for
protocol editing, check the sender's
packet format to see if an incorrect
value is set for Code type or Data
length of the check code.
 Check and correct the external device
transmit message and restart data
PRO
communications.
MELSEC-Q
Protocol
Non
Bidire- Pre-
MC Proce-
ctional defined
dure
11 - 25