RS232 - Interface
BC8050 und BC8150
64
Version: 3.0.0
6
RS232 - Interface
6.1
Protocol
6.1.1
Modbus
6.1.1.1
Modbus protocol
RTU
In RTU mode the protocol starts with a pause of 3.5 characters, and finishes in the same way (illustrated in
the diagram with T1-T2-T3-T4).
The characters permitted for transmission in all fields are hexadecimal 0... 9, A..., F.
Start
Slave address
Function
Data
CRC
END
t1-t2-t3-t4
1 byte
1 byte
n Bytes
2 bytes
t1-t2-t3-t4
ASCII
In ASCII mode the telegram starts with a colon (":", character 0x3A) and ends with a
carriage return line feed
("CRLF", characters 0x0D and 0x0A).
The characters transferred are represented in the ASCII code.
Start
Slave address
Function
Data
LRC
END
1 byte 0x3A
2 bytes
2 bytes
n Bytes
2 bytes
2 bytes 0x0D,
0x0A
6.1.1.2
Data Frame
Description
ModbusRTU (address 40-59) DEFAULT
ModbusASCII (address 1-39) DEFAULT
Data bits
8
8
Stop bits
1
1
Baud rate
9600 baud
38400 baud (automatic detection)
Parity
none
even
Summary of Contents for BC8050
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