Advanced Videographic Recorder
SM2000
Appendix B – Modbus Guide
116
IM/SM2000
Issue 11
B.6 Operating Mode Modbus Registers
Tables B.15 to B.21 detail the contents of the Modbus registers
accessible while the instrument is in the operating mode.
Two data types are used:
32-bit single precision floating point data in IEEE format
64-bit double precision floating point data in IEEE format
Note.
When writing to a parameter that occupies more than
one register position then all registers relating to that
parameter MUST be written to as part of a multiple
register write. If this is not achieved a NAK exception
response is issued. Individual registers can be read
without causing an exception response.
When accessing a parameter that occupies more than
one register position, the lowest numbered register
contains the most significant data.
Analog Inputs
Modbus Registers
Read only, single precision floating point
number –999 to +9999
A1
0001 and 0002
A2
0003 and 0004
A3
0005 and 0006
A4
0007 and 0008
A5
0009 and 0010
A6
0011 and 0012
B1
0013 and 0014
B2
0015 and 0016
B3
0017 and 0018
B4
0019 and 0020
B5
0021 and 0022
B6
0023 and 0024
Reserved
0025 to 0100
Table B.15 Analog Inputs
Trip Point Registers
(single precision floating point)
Read: –999 to +9999
Alarm Number and Name
Write: –999 to +9999
1
Alarm 1.1A
0101 and 0102
2
Alarm 1.1B
0103 and 0104
3
Alarm 1.2A
0105 and 0106
4
Alarm 1.2B
0107 and 0108
5
Alarm 1.3A
0109 and 0110
6
Alarm 1.3B
0111 and 0112
7
Alarm 1.4A
0113 and 0114
8
Alarm 1.4B
0115 and 0116
9
Alarm 1.5A
0117 and 0118
10
Alarm 1.5B
0119 and 0120
11
Alarm 1.6A
0121 and 0122
12
Alarm 1.6B
0123 and 0124
13
Alarm 2.1A
0125 and 0126
14
Alarm 2.1B
0127 and 0128
15
Alarm 2.2A
0129 and 0130
16
Alarm 2.2B
0131 and 0132
17
Alarm 2.3A
0133 and 0134
18
Alarm 2.3B
0135 and 0136
19
Alarm 2.4A
0137 and 0138
20
Alarm 2.4B
0139 and 0140
21
Alarm 2.5A
0141 and 0142
22
Alarm 2.5B
0143 and 0144
23
Alarm 2.6A
0145 and 0146
24
Alarm 2.6B
0147 and 0148
Reserved
0149 to 0250
Table B.16 Alarm Trip Levels
Math Block Number
Modbus Registers
Math Block 1 Result
0901 and 0902
Math Block 2 Result
0903 and 0904
Math Block 3 Result
0905 and 0906
Math Block 4 Result
0907 and 0908
Math Block 5 Result
0909 and 0910
Math Block 6 Result
0911 and 0912
Math Block 7 Result
0913 and 0914
Math Block 8 Result
0915 and 0916
Math Block 9 Result
0917 and 0918
Math Block 10 Result
0919 and 0920
Math Block 11 Result
0921 and 0922
Math Block 12 Result
0923 and 0924
Table B.17 Math Block Results