LPGmass Modbus RS485
System integration
Hauser
37
Code
Name
Description
Application
06
Write single
registers
Master writes a new value to
one
Modbus register of the measuring
device.
Use function code 16 to write
multiple registers with just 1
telegram.
Write only 1 device parameter
Example: reset totalizer
08
Diagnostics
Master checks the communication
connection to the measuring device.
The following "Diagnostics codes"
are supported:
• Sub-function 00 = Return query
data (loopback test)
• Sub-function 02 = Return
diagnostics register
16
Write multiple
registers
Master writes a new value to
multiple Modbus registers of the
device.
A maximum of 120 consecutive
registers can be written with 1
telegram.
If the required device
parameters are not available
as a group, yet must
nevertheless be addressed
with a single telegram, use
Modbus data map → 37
Write multiple device parameters
Example:
• Mass flow unit
• Mass unit
23
Read/Write
multiple
registers
Master reads and writes a
maximum of 118 Modbus registers
of the measuring device
simultaneously with 1 telegram.
Write access is executed
before
read access.
Write and read multiple device
parameters
Example:
• Read mass flow
• Reset totalizer
Broadcast messages are only allowed with function codes 06, 16 and 23.
9.2.2
Register information
For an overview of device parameters with their respective Modbus register
information, please refer to the "Modbus RS485 register information" section in the
"Description of device parameters" documentation → 85.
9.2.3
Response time
Response time of the measuring device to the request telegram of the Modbus master:
typically 3 to 5 ms
9.2.4
Modbus data map
Function of the Modbus data map
The device offers a special memory area, the Modbus data map (for a maximum of 16
device parameters), to allow users to call up multiple device parameters via Modbus RS485
and not only individual device parameters or a group of consecutive device parameters.
Grouping of device parameters is flexible and the Modbus master can read or write to the
entire data block simultaneously with a single request telegram.
