NOVUS RHT-P10-485-LCD - Manual (Page 4)

RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD Transmitters
NOVUS AUTOMATION 4/6
Read-only screens of the values measured by the transmitter:
5ª Screen: Temperature
6ª Screen: Relative Humidity
7ª Screen: Dew Point
6 SERIAL COMMUNICATION
The transmitter is provided with RS485 serial communication, operating as a
slave within the Modbus RTU network. The configuration of the transmitter is
performed through the serial (RS485) interface. For configuring the
communication parameters you can use the programming
button.
In this section you will find the instructions necessary to perform the data
reading without using the DigiConfig software. In order to assure correct
configuration of the transmitter, always use the DigiConfig software. After
being configured, the input data may be accessed by any other software
capable for Modbus RTU communication.
6.1 MODBUS COMMANDS
The Modbus RTU commands (functions) listed in the table below are
implemented. For further information with respect to each of these
commands and the Modbus protocol in general, please access the site
www.modbus.org.
READ HOLDING REGISTERS – 0x03
This command can be used for reading the value of one or several holding
registers, according to the “Holding Registers Table”.
WRITE HOLDING REGISTERS – 0x06
This command can be used for writing in a holding register, according to the
“Holding Registers Table”.
6.2 DESCRIPTION OF SOME REGISTERS
REGISTER 2 – BAUD-RATE
Defines the Modbus communication speed. The transmitter comes factory-
configured with a Baud-Rate of 1200.
Code Baud-rate
0 1.200
1 2.400
2 4.800
3 9.600
4 19.200
5 38.400
6 57.600
7 115.200
REGISTER 3 – MODBUS ADDRESS
Defines the address of the transmitter within the Modbus network. Values
between 1 and 247. The transmitter comes factory-configured with address
247.
REGISTER 4 – PARITY
Defines the parity code used for Modbus communication. The transmitter
comes factory-configured with parity even.
Code Parity
0 None
1 Odd
2 Even