Vortex IR610 Series, Руководство пользователя

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IR610 high performance vector control frequency inverter user manualAppendix A Modbus communication protocol
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information can be returned and the slave device times out.
(3) If the slave device receives a request and detects a communication error (parity,
address, framing error, etc.), no response is returned and the slave device times out.
(4) If the slave device receives no communication error request, but can not handle the
request (such as the register address does not exist, etc.), the slave station will return an
abnormal response to inform the master of the actual situation.
Abnormal response command code = normal response command code + 0x80,
Abnormal code value and meaning as shown in the following table
Error
code
Name Description
0x01 Invalid command code/error
function code
The function code received by the slave is outside the
configured range
0x02 Error data address/Illegal
register address
Slave station receives the data address is not allowed
address
the number of registers being Read and write is out of
range
When writing multiple registers, the number of bytes in
the PDU is not equal to the number of registers
0x03 wrong frame format Length of frame is not correct
CRC verifying not passed
0x04 Data is out of range The data received by the slave exceeds the
corresponding register minimum to maximum range
0x05 Reading request refuse Operate to read-only register wirte
Operate to read-only register write in running status
A.5 CRC check
CRC
（
Cyclical Redundancy Check
）
use RTU frame
，
The message includes an error detection field
based on the CRC method. The CRC field examines the contents of the entire message. The CRC field
is two bytes containing a binary value of 16 bits. It is calculated by the transmission equipment and
added to the message. The receiving device recalculates the CRC of the received message and
compares it with the value in the received CRC field,If the two CRC values are not equal, there is an
error in the transmission.There is a lot of information on the Internet about CRC checking it is not
elaborated hereabout CRC check code generation algorithm,
A.6 Register address distribution
The register address of IR610 is 16-bit data, the upper 8 bits represent the function code group