Section 7 | Communications
©
2023
–
Valeport Ltd
Page | 22
7.4.1
Modbus Register Lookup Table
# Code followed by
Description
Type
Modbus
Register
Hex
Modbus
Register
Dec
Number of
Modbus
2 byte registers
Reply timing @
19200 Baud
(in ms)
#001
;address_485<CR><LF>
Set the address value for addressed system
This is also the Modbus address for the
instrument
F_UCHAR
0x0022
34
1
<40
#002
<CR><LF>
Reads the address value for addressed system
F_UCHAR
0x0022
34
1
<40
#005
;address_mode<CR><LF>
Turns on or off address mode 0 = OFF 1 = ON
F_UCHAR
0x0023
35
1
<40
#006
<CR><LF>
Reads address mode ON or OFF
F_UCHAR
0x0023
35
1
<40
#022
<CR><LF>
Reads ASCII string of the last calibration date:
Format
–
day;month;year
F_UCHAR
0x0002
2
2
<40
#034
<CR><LF>
Reads the serial number of the instrument
F_ULONG
0x0030
48
2
<40
#037
;site_info<CR><LF>
Enter site information
F_ASCII
0x0020
32
30
<40
#038
<CR><LF>
Read the site information
F_ASCII
0x0020
32
30
<40
#039
;sampling mode
<CR><LF>
Set the last sampling mode set without running F_ASCII
0x001F
31
4
<40
#040
sampling mode
Read last sampling mode set
F_ASCII
0x001F
31
4
<40
#059
;baud_rate<CR><LF>
Baud rate. 2400,4800,9600,19200,115200 or
230400
F_ULONG
0x001A
26
2
<40
#060
<CR><LF>
Read Baud rate
F_ULONG
0x001A
26
2
<40
#082
;rs_485_selected<CR><LF>
Selects if in RS485 mode.
Usually done with control line (MK1 PCB only)
F_UCHAR
0x0024
36
1
<40
#083
<CR><LF>
Read status
F_UCHAR
0x0024
36
1
<40
#086
;secondary_calibration_enabled
<CR><LF>
Secondary calibration status 0 = disabled, 1 =
enabled.
F_USHORT
0x0038
56
1
<40
#087
<CR><LF>
Read Secondary calibration 0 = disabled, 1 =
enabled.
F_USHORT
0x0038
56
1
<40
#094
;gain;offset<CR><LF>
Set offset and gain coefficient for a user
secondary calibration - optics channel 1
F_EXP
0x0036
54
4
<40
#095 <CR><LF>
Read offset and gain coefficient
F_EXP
0x0036
54
4
<40