7. Interfaces and Communication
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The frame format is described in the following table.
Frame header (START) Greater than the 3.5-byte transmission idle time
Slave address (ADR) Communication address : 1 to 247
0: Broadcast address
Command code (CMD) 03:Read slave parameters
06: Write slave parameters
Function code address (H) It is the internal parameter address of the AC drive, expressed
in hexadecimal format. The parameters include functional
parameters and non-functional parameters (running status and
running command). During transmission, low-order bytes follow
the high-order bytes.
Function code address (L)
Number of function codes (H) It is the number of function codes read by this frame. If it is 1,
it indicates that one function code is read. During transmission,
low bytes follow high bytes.
In the present protocol, only one function code is read once, and
this eld is unavailable.
Number of function codes (L)
Data (H) It is the response data or data to be written. During transmission,
low-order bytes follow the high-order bytes.
Data (L)
CRC CHK high bytes It is the detection value (CRC16 verication value). During
transmission, low-order bytes follow the high-order bytes.
CRC CHK low bytes
END It is 3.5-byte transmission time.