Gill Instruments Ltd
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MetPak/MetPak RG and MetPak Pro Base Stations
Page | 72
Issue 1
Doc. No. 1723-PS-0023
October 2018
Base Station MODBUS NOTES
To work out Modbus register numbers applicable to a Base Station parameter, start out
with setting up the Base Station in ASCII mode and determining which parameters are to
be output, and the exact order that they are to be output before setting to Modbus Comms.
Refer to the Modbus output parameter tables (shows 2 axis Base Stations) below to
determine how many registers each chosen parameter will take up.
Fill up the register table, starting at 40001, with the required output parameters in
the order in which they will be output.
Note:
After powering up the Base Station, wait 10 seconds before requesting any
measurements.
MetPak Base Station
Output Parameters
Type
No. of
Registers
Register Numbers
NODE
4 Bit Character String
2
40001-2
DIRECTION
32 Bit Floating Point Value
2
40003-4
SPEED
32 Bit Floating Point Value
2
40004-5
PRESSURE
32 Bit Floating Point Value
2
40006-7
RELATIVE HUMIDITY
32 Bit Floating Point Value
2
40008-9
TEMPERATURE
32 Bit Floating Point Value
2
40010-11
DEWPOINT
32 Bit Floating Point Value
2
40012-13
SUPPLY VOLTAGE
32 Bit Floating Point Value
2
40014-15
STATUS
32 Bit Unsigned Integer (UINT)
2
40016-17
MetPak RG Base Station
Output Parameters
Type
No. of
Registers
Register Numbers
NODE
4 Bit Character String
2
40001-2
DIRECTION
32 Bit Floating Point Value
2
40003-4
SPEED
32 Bit Floating Point Value
2
40005-6
PRESSURE
32 Bit Floating Point Value
2
40007-8
RELATIVE HUMIDITY
32 Bit Floating Point Value
2
40009-10
TEMPERATURE
32 Bit Floating Point Value
2
40011-12
DEWPOINT
32 Bit Floating Point Value
2
40013-14
DIG1
32 Bit Floating Point Value
2
40015-16
SUPPLY VOLTAGE
32 Bit Floating Point Value
2
40017-18
STATUS
32 Bit Unsigned Integer (UINT)
2
40019-20
MetPak Pro Base Station
Output Parameters
Type
No. of
Registers
Register
Numbers
NODE
4 Bit Character String
2
40001-2
DIRECTION
32 Bit Floating Point Value
2
40003-4
SPEED
32 Bit Floating Point Value
2
40005-6
PRESSURE
32 Bit Floating Point Value
2
40007-8
RELATIVE HUMIDITY
32 Bit Floating Point Value
2
40009-10
TEMPERATURE
32 Bit Floating Point Value
2
40011-12
DEWPOINT
32 Bit Floating Point Value
2
40013-14
PRT
32 Bit Floating Point Value
2
40015-16
AN1
32 Bit Floating Point Value
2
40017-18
AN2
32 Bit Floating Point Value
2
40019-20
DIG1
32 Bit Floating Point Value
2
40021-22
SUPPLY VOLTAGE
32 Bit Floating Point Value
2
40023-24
STATUS
32 Bit Unsigned Integer (UINT)
2
40025-26
