Mitsubishi QJ71MB91, User Manual

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4
MODBUS(R) STANDARD FUNCTIONS
4.1 MODBUS(R) Standard Function Support List
4
- 2
1
O
VER
VIE
W
2
SYS
T
E
M
CO
NF
IG
U
R
A
T
IO
N
3
S
P
E
CIFICA
TI
ONS
4
MODB
US
(R)
S
TAN
DAR
D
FUN
C
TIO
N
S
5
FUNC
TI
ON
6
PR
E
-O
PER
A
T
ION
AL
P
R
OCED
URE
S A
ND
SE
TTINGS
7
P
A
RA
MET
E
R S
E
TTI
N
G
8
UTIL
ITY P
A
CK
AGE
(G
X Co
nf
ig
u
rat
o
r-M
B)
Table4.1 MODBUS standard function support list (continued)
(Continued on next page)
Function
code
(Sub code)
Sub-function
code
Function Description
Accessible
devices
per
message
Broadcast Reference
08
00 Return query data
Returns the contents of the request
message without change.
Used to check if the network or the
target device is operating normally.
(Loopback test)
-
Section
4.11.1
01
Restart communications
option
Initializes the communication port of the
receiving channel side and restarts the
slave function. (Clears counters such
as the message count.)
Returns to the online mode when it is in
the listen only mode.
-
Section
4.11.2
02
Return diagnostic
register Reads out the detailed LED status of
the QJ71MB91 to the master.
-
Section
4.11.3
03
Change ASCII input
delimiter
Changes the 2nd byte (LF(0A
H
)) of the
end code in the ASCII mode to a
specified data. -
Section
4.11.4
04 Force listen only mode
Places a slave into the offline mode.
Used when disconnecting a slave from
the network.
-
Section
4.11.5
10
Clear counters and
diagnostic register
Clears counters (e.g. message count).
Also, clears the diagnostic register and
the error of the channel where the
request message has been received.
-
Section
4.11.6
11
Return bus message
count Reads out the number of messages
detected on the line to the master.
-
Section
4.11.7
12
Return bus
communication error
count Reads out the number of error
messages detected on the line to the
master.
-
Section
4.11.8
13
Return bus exception
error count Reads out the frequency of exception
errors to the master.
-
Section
4.11.9
14
Return slave message
count
Reads out the number of the slave
message processing to the master.
(Including reception of broadcast
request messages)
-
Section
4.11.10
15
Return slave no
response count
Reads out the number of broadcast
request messages received to the
master.
-
Section
4.11.11