Modbus (Rtu Mode) For Temperature Control Unit, Etc - Panasonic GT Series Manual

10.3 Modbus (RTU Mode) for Temperature Control Unit,
etc
PLC model selection
Device setting: Start No. *****0
Select "Modbus (RTU mode | Temperature control unit, etc)
Overview of communication
Only function codes "03" and "06" which are the command to read/write the contents of the holding
registers are used. The function code "03" is a message to enable the contents of multiple holding
registers to be read, however, GT reads the number of holding registers by 1 word.
For outputting bit, read the value of the holding register to be output and change the bit before writing.
Usable devices
Bit/Word Device
Bit Device Holding register
Word Device Holding Register
Communication Parameters Settings
The example of communication settings of GT and a device such as temperature control unit is shown
below.
Setting Values for GT (Set in the configuration setting of GTWIN.)
Item
PLC Unit No.
Baud Rate
Length of Bits
Stop Bits
Parity
Setting Values for Temperature control unit, etc
Item
Station Address
Mode
Baud Rate
Length of Bits
Stop Bits
Parity
Precautions when making communication settings
When connecting the GT via RS485, set the transmission delay in GT Configuration to 5 ms or more.
(The appropriate values vary according to equipment to be connected. Check with actual equipment.)
10-4
400000.0-465535.F
400000-465535
Setting
1
19200bps
8
1
Even
Setting
1
RTU
19200bps
8
1
Even
No.