4.4.5 SDI-12 Interface for the B2 and S2 Models
The SDI-12 interface on the B2 Wireless Controllers can support up to five
devices with twelve 32-bit register values each. The SDI-12 interface can
be configured to increase the number of registers per device address for
devices with large register sets. The factory default enables one SDI-12
device using device address 1 with up to nine registers with a SDI-12
command of "M!".
Use the configuration software to adjust the SDI-12 parameters.
power
ground
serial
SD
GD
SP
SDI-12
device
B2
Controller
Basic SDI-12 Interface Parameters
Up to five devices/commands can be accessed using the SDI-12 interface. There are three parameters for each device/
command: Enable, Device Address, Device Command. For more information, refer to the SDI-12 Technical Notes.
Enable
. Instructs the DXM100 device to activate or deactivate the SDI-12 device. Write a 1 to enable, and write a 0 to
disable. The factory default for device 1 is enabled; devices 2 through 5 are disabled.
Device Address
. Each SDI-12 device must have a unique device address. This parameter is the ASCII code for the device
address. Valid device addresses are
0–9
and
a–z
that map to ASCII codes
48–57
and
97–122
, respectively. The factory
default addresses are:
•
SDI-12 Device 0 uses ASCII code 48
•
SDI-12 Device 1 uses ASCII code 49
•
SDI-12 Device 2 uses ASCII code 50
•
SDI-12 Device 3 uses ASCII code 51
•
SDI-12 Device 4 uses ASCII code 52
Device Command
The SDI-12 interface supports "M!" or "C!" commands. Use the Device Command parameter to define
which command to use for this device. The factory default is "M!" commands for all devices (value of 10 in the Modbus
register).
Supported M! Commands
SDI-12 Command
Register Value
xM!
0 or 10
xM1!
11
xM2!
12
xM3!
13
xM4!
14
xM5!
15
xM6!
16
xM7!
17
xM8!
18
xM9!
19
Supported C! Commands
SDI-12 Command
Register Value
xC!
1 or 20
xC1!
21
xC2!
22
xC3!
23
xC4!
24
xC5!
25
xC6!
26
xC7!
27
xC8!
28
xC9!
29
The Modbus configuration registers are listed. All registers are defined as Modbus holding registers. The factory default
values are shown in parentheses. All values are in decimal, unless noted otherwise.
Device/CMD Configuration
Registers (Default Value)
Enable
Device Address
Device Command
SDI-12 Device/CMD 1
1751 (1)
11001 (48) 5
11002 (10)
SDI-12 Device/CMD 2
1701 (0)
11201 (49)
11202 (10)
SDI-12 Device/CMD 3
1651 (0)
11401 (50)
11402 (10)
5 The default device addresses 48 through 52 are in ASCII.
Sure Cross
®
DXM100-Sx Wireless Modbus Slave
www.bannerengineering.com - Tel: + 1 888 373 6767
21