LS LSLV-iV5 Series, Руководство пользователя

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Chapter 8 Communication Function
8-5
8.6 Communication Protocol
8.6.1 LS INV 485 protocol
Computer and other hosts are the master and the inverter is the slave. The slave inverter responds to the master’s re quest for
writing/reading.
[Basic Form]
Request:
ENQ Address No. CMD Data SUM EOT
1 byte 2 bytes 1 byte n bytes 2 bytes 1 byte
Normal Response:
ACK Address No. CMD Data SUM EOT
1 byte 2 bytes 1 byte n * 4 bytes 2 bytes 1 byte
Error response:
NAK Address No. CMD Error Code SUM EOT
1 byte 2 bytes 1 byte 2 bytes 2 bytes 1 byte
Description:
Requests begin with ENQ and end with EOT.
Normal responses begin with ACK and ends with EOT.
Error responses begin with NAK and ends with EOT.
Address No. refers to the inverter No. and represented by 2 byte ASCII-HEX.
(ASCII- HEX: hex representation consisting of ‘0’ ~ ‘9’, ‘A’ ~ ‘F’)
CMD: in capitals (IF Error if in small letters)
Character ASCII-HEX Command
‘R’ 52h Read
‘W’ 57h Write
‘X’ 58h Monitor registration request
‘Y’ 59h Monitor registration implementation
Data: represented in ASCII-HEX
E.g.) If data value is 3,000: 3000
→
‘0’’B’’B’’8’h
→
30h 42h 42h 38h
Error code: two can be displayed ASCII (20h ~ 7Fh)
Transmission/reception buffer magnitude: transmission = 39 byte, reception = 44 byte
Monitor registration buffer: 8 Word
SUM: inspection by making sum to check communication errors
SUM = ASCII-HEX form of the 8 lowest bits of (Address No. + CMD + data)