INVT GD310-011P-4-UL, Operation Manual

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GD310-UL series VFD Communication protocol
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For example, write 5000 (1388H) to 0004H from the VFD with the address of 02H, the frame structure
is as below:
RTU master command message (from the master to the VFD)
START T1-T2-T3-T4 (transmission time of 3.5 bytes)
ADDR 02H
CMD 06H
High bit of writing data address 00H
Low bit of writing data address 04H
Data content
13H
Data content
88H
Low bit of CRC C5H
High bit of CRC 6EH
END T1-T2-T3-T4 (transmission time of 3.5 bytes)
RTU slave response message (from the VFD to the master)
START T1-T2-T3-T4 (transmission time of 3.5 bytes)
ADDR 02H
CMD 06H
High bit of writing data address 00H
Low bit of writing data address 04H
High bit of data content
13H
Low bit of data content
88H
Low bit of CRC C5H
High bit of CRC 6EH
END T1-T2-T3-T4 (transmission time of 3.5 bytes)
Note: Section 10.4.1 and 10.4.2 mainly describe the command format, and the detailed application
will be mentioned in 10.4.8 with examples.
10.4.3 Command code 08H for diagnosis
Meaning of sub-function codes
Sub-function Code Description
0000 Return to inquire information data
For example: The inquiry information string is same as the response information string when the loop
detection to address 01H of driver is carried out.
The RTU request command is:
START T1-T2-T3-T4 (transmission time of 3.5 bytes)
ADDR 01H