New Cosmos Electric PS-7-M, Руководство по техническим характеристикам связи

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Message frame Modbus TCP Modbus RTU Remarks
Data item Data
size
(byte) No. Byte
data Hex No. Byte
data Hex
Data1 Hi 2 (18) 1 0x00 – – – Write by the
word
Lo (19) 0x01 – –
Data2 Hi 2
(20) 25 0x00 – – –
Lo (21) 0x19 – –
Error
check
data Lo 2 – – – – – –
Hi – – – – – –
Example of response message
The slave returns a response message including the “current gas concentration = 25%F.S. (0x0019)
and F.S. code = 101 (0x0065)” to the master.
Message frame Modbus TCP Modbus RTU Remarks
Data item Data
size
(byte) No. Byte
data Hex No. Byte
data Hex
TRXN
ID Hi 2 (1) 0 0x00 – – –
Lo (2) 0 0x00 – – –
Protocol
ID Hi 2 (3) 0 0x00 – – – Fixed at “00”.
Lo (4) 0 0x00 – – –
Quantity
of
comm.
data Hi 2 (5) 13 0x00 – – – Number of data
which follows
unit ID
Lo (6) 0x0D – – –
Unit ID 1 (7) 1 0x01 – – –
Function code 1 (8) 3 0x03 – – –
Quantity of
data 1 (9) 4 0x04
– – – Quantity of
response data =
N x 2 bytes
N: Quantity of
registers
N range= 1–125
Data1
Hi 2
(10) 25 0x00 – – – Sent by the byte
in the sequence
of high-order
byte followed
by low-order
byte: Data 1, 2,
3, 4….
Lo (11) 0x19 – –
Data2 Hi 2 (12) 101 0x00 – – –
Lo (13) 0x65 – –
Error
check
data Lo 2 – – – – – –
Hi – – – – – –