Modbus Registers; Measurement Data Registers; Status Registers - Vaisala CARBOCAP GMW80 Series Quick Manual

Value
8002 ... FFFF
hex hex
8000
hex
The 16-bit integer value for measured temperature in
the necessary decimals.

Modbus registers

CAUTION!
addresses in actual Modbus messages (Modbus Protocol Data Unit (PDU)) are in
hexadecimal and start from zero. Subtract 1 from the register number presented
in this manual to get the address used in the Modbus message (for example,
register number 1 corresponds to address 0
Accessing unavailable (temporarily missing) measurement data does not generate a Modbus
exception. "Unavailable" value (a quiet NaN for floating point data or 8000
is returned instead. An exception is generated only for any access outside the applicable
register ranges.

Measurement data registers

Table 4 Modbus measurement data registers (read-only)
Register Address
number
1 0000
hex
5 0004
hex
257 0100
hex
259 0102
hex

Status registers

Table 5 Modbus status registers (read-only)
Register Address
number
513 0200
hex
514 0201
hex
10
Registers are numbered in decimal, starting from 1. Register
Register description
Measured CO value
2
Measured temperature
Measured CO value
2
Measured temperature (T * 10) 16-bit integer
Register description
Device status
Error code
Description
Value in range -32766 ... -1 (2's complement)
Value is not available
Table 4 (page 10)
in the actual Modbus message).
hex
Data format
32-bit float
32-bit float
16-bit integer
Data Notes
format
16-bit 0000 : Status OK; if other values
hex
integer
are returned, see
(page 8).
32-bit Used by Vaisala Technical Support
integer when solving device problems
is scaled to include
for integer data)
hex
Unit
ppm
°C
ppm
°C
Troubleshooting
M212445EN-A