Circutor DHC-96 CPM, Instruction Manual

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39
Instruction Manual
DHC-96 CPM 1500
6�2�- MODBUS PROTOCOL
In the Modbus protocol, the
DHC-96 CPM 1500
device uses the RTU (Remote Terminal Unit) mode.
The Modbus functions implemented in the device are as follows:
Function 0x01 : Reading a relay.
Function 0x02 : Reading input status.
Function 0x03
and
0x04
: Reading integer registers.
Function 0x05 : Writing a relay.
Function 0x0F
: Writing multiples relays
Function 0x10 : Writing multiples registers.
6�2�1� READING EXAMPLE: FUNCTION 0x01�
Question:
Status of output relays
Address Function
Initial
Register
No� of
Registers
CRC
01 01 0000 0002 BDCB
Address: 01
, Peripheral number: 1 in decimal.
Function: 01 , Read function.
Initial Register: 0000
, on which the reading will start.
No� of Registers: 0002 , number of registers read.
CRC: BDCB , CRC Character.
Response:
Address Function No� of Bytes Register No� 1 Register No� 2 CRC
01 01 01 0001 0000 6611
Address: 01 , Responding peripheral number: 1 in decimal.
Function: 01 , Read function.
No� of bytes: 01
, No. of bytes received.
Registre No 1: 0001 , output relays 1 closed.
Registre No 2: 0000
, output relays 2 open.
CRC:6611 , CRC.Character.
6�2�2� EXAMPLE OF OPERATION OF THE REMOTE CONTROL: FUNCTION 0x05�
Question:
Activate the output of relay 1, programmed to work in remote control mode.
Address Function
Initial
Register
Relay action CRC
01 05 0000 FF00 8C3A
Address: 01
, Peripheral number: 1 in decimal.
Function: 05 , Writing a relay
Initial Register: 0000
, relay 1 address.
Relay action: FF00 , We indicate that we want to close the relay.