User's Manual

9
Remote Modbus Register Mapping
The Scout Node sends data to a SignalFire Telemetry Modbus Gateway. The data that is
sent to the gateway is available at the gateway in registers where it can then be read by a Modbus RTU.
Consequently, the node needs to have a unique (to the network it is in) Modbus slave ID which the gateway
will use to store its unique data.
Modbus Registers
Every check-in period, the sensors are read and data is sent to the gateway. The gateway will save the data
under the set Modbus ID in 16-bit registers. The register map for this system is below.
Register Map
Register
Number
Register
Address
(Offset)
Description
43001
3000
Sensor Voltage (mV) (500mV to 2500mV is normal range)
43002
3001
Sensor PSI Reading (int)
43003
3002
Sensor PSI Reading x 100 (int) (only valid for pressures up to 650psi)
43004
3003
High Alarm Notification (0 = no alarm, 1 = high alarm active)
43005
3004
Low Alarm Notification (0 = no alarm, 1 = low alarm active)
43006
3005
Low Battery Alarm (0 = battery above 3.0V, 1 = battery below 3.0V)
43007
3006
Sensor Span (PSI)
43008
3007
Sensor Error Status (0=no errors, 1=sensor out of range low, 2=sensor out
of range high)
43009-43010
3008-3009
Sensor PSI Reading (float)
43011-43012
3010-3011
Custom Scaled Sensor Reading (float)
43013-43014
3012-3013
Alarm High Threshold Setting (float)
43015-43016
3014-3015
Alarm Low Threshold Setting (float)
49988
9987 or 65524
Major revision number for the mainboard
49989
9988 or 65525
Minor revision number for the mainboard
49990
9989 or 65526
Major revision number for the radio
49991
9990 or 65527
Minor revision number for the radio
49992
9991 or 65528
High 16 bits of SFTS node address
49993
9992 or 65529
Low 16 bits of SFTS node address (the radio ID)
49994
9993 or 65530
Slave ID readback
49995
9994 or 65531
Received signal strength of last packet from the slave
49996
9995 or 65532
Battery voltage of the Modbus client, in millivolts
49997
9996 or 65533
Minutes until this slave will time out, unless new data is received
49998
9997 or 65534
Number of registers cached for this slave device
49999
9998 or 65535
Remote device type. ?? for Pressure Scout
SignalFire Telemetry
Rev 1.1