Mitsubishi QJ71MB91, User Manual

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4
MODBUS(R) STANDARD FUNCTIONS
4.17 Read File Record (FC: 20) (SC: 06)
4
- 56
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
TA
NDA
RD
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)
(2) Response message format (Slave Master)
(When completed normally)
"N" in the above diagram represents the total of the device data (n1 +...+ nm).
(When completed with an error)
* 1 Exception and error codes are stored in the buffer memory in the case of error completion.
Refer to the following for storage location, confirmation methods, and detailed contents.
Section 11.4
Figure 4.92 Read file record (Normal response message)
Figure 4.93 Read file record (Exception message)
Data
(L) (L)
Sub-request 1
Data
(L) (L)
Function code
Function
code
(14
H
)
Number of
response data
bytes
(m x 2 + N x 2)
Read bytes
(n1 x 2 + 1)
Reference
number
(06
H
)
Device
data
1
Device
data
n1
(Number of read bytes n1 x 2 + 1)
(Number of response data bytes m x 2 + N x 2)
Sub-request m
Number of
read bytes
(nm x 2 + 1)
Reference
number
(06
H
)
Device
data
1
Device
data
nm
(Number of read bytes nm x 2 + 1)
(Number of response data bytes m x 2 + N x 2)
(H) (H)
(H)
(H)
Data Function code
Function
code
(94
H
)
Exception
code* 1