RKI Instruments M2 Rig Monitor - Manual (Page 43)

M2 Rig Monitor Operator’s Manual 38
return to the first adjustable parameter. Go back to step 3 and continue.
If you want to save the adjustments made, press and release the UP/YES button.
Modbus Saved
is indicated on the display for a few seconds and the M2 Rig Monitor
returns to normal operation.
NOTE: All M2 Rig Monitors on a Modbus network must be configured with the same
baud rate and parity, and each M2 Rig Monitor must have a unique slave ID.
For an M2 Rig Monitor to participate on a network, the ENABLED/DISABLED
setting must be set to ENABLE.
Supported Modbus Functions
The Rig Monitor supports Function Code 03: Read Holding Registers and Function Code
16: Write Registers. The register assignments detailed below were implemented in Rig
Monitor firmware version 5.0. Please see revision B of the M2 manual if you have an M2
Rig Monitor with a firmware version previous to 5.0.
WARNING: Do not attempt to use registers according to the instructions below with
units that have firmware versions previous to 5.0. For the Modbus register
assignments of M2 Rig Monitors with firmware previous to 5.0, see
revision B of the M2 Operator’s Manual. The firmware version is shown
on the Information Screen described on page 17.
Function Code 03: Read Holding Registers
There are a total of 40 registers available to be read via this Function Code.
Registers 1 - 2
The format (bit & field assignments) for registers 1 - 2 is shown below in Table 8 - Table 9.
Table 8: Register 1, Numerical Reading with Sign & Decimal Point Bit & Field Assignments
Bit(s) Value & Field
[15] Sign of Reading
0 = Positive
1 = Negative
[14:13] Format of Reading
0 = XXX (no decimal point)
1 = XX.X
2 = X.XX
3 = .XXX
[12:0] Numerical value of display reading (8000 max)