SM3000
Multipoint Videographic Recorder
Appendix B – Modbus Guide
132
IM/SM3000–EN Rev. L
B.3.2 Modbus Exception Responses
If the instrument detects one of the errors listed in Table B.1
while receiving a message from the host system, it replies with a
response message consisting of the instrument's Modbus
address, the function code, the error code and error check
fields.
B.4 Operating Mode
B.4.1 Operating Mode Modbus Coils
Tables B.2 to B.17 detail the contents of each Modbus coil.
Each coil is assigned a register that can have one of two values:
0000 or 0001.
Code
Name
Definition
01
Illegal Function
The message function received is
not an allowable action
02
Illegal Data Address
The address reference in the data
field is not an allowable address
03
Illegal Data Value
The value referenced in the data
field is not allowable in the
addressed slave
07
Negative
Acknowledgment
Received message error
08
Memory Parity Error
Parity check indicates an error in
one or more of the characters
received
Table B.1 Modbus Exception Responses
Analog
Input
Modbus Coil
(Read Only)
0 = Input OK
1 = Input failed
Analog
Input
Modbus Coil
(Read Only)
0 = Input OK
1 = Input failed
A1
0001
D1
0019
A2
0002
D2
0020
A3
0003
D3
0021
A4
0004
D4
0022
A5
0005
D5
0023
A6
0006
D6
0024
B1
0007
E1
0025
B2
0008
E2
0026
B3
0009
E3
0027
B4
0010
E4
0028
B5
0011
E5
0029
B6
0012
E6
0030
C1
0013
F1
0031
C2
0014
F2
0032
C3
0015
F3
0033
C4
0016
F4
0034
C5
0017
F5
0035
C6
0018
F6
0036
Table B.2 Analog Input Fail States