LSIS 6731001500, User Manual

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RS-485 Communication Features
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Data: ASCII-HEX (for example, when the data value is 3000: 3000 → ‘0’’B’’B’’8’h → 30h 42h
42h 38h)
•
Error code: ASCII-HEX (refer to
7.3.6.4 Error Code
on page
371)
•
Transmission/reception buffer size: Transmission=39 bytes, Reception=44 bytes
•
Monitor registration buffer: 8 Words
•
SUM: Checks communication errors via sum.
•
SUM=a total of the lower 8 bits values for station ID, command and data (Station
ID+CMD+Data) in ASCII-HEX.
•
For example, a command to read 1 address from address 3000:
SUM=‘0’+‘1’+’R’+‘3’+‘0’+‘0’+‘0’+’1’ = 30h+31h+52h+33h+30h+30h+30h+31h = 1A7h (the
control value is not included: ENQ, ACK, NAK, etc
ENQ Station ID CMD Address Number of Addresses SUM EOT
05h ‘01’ ‘R’ ‘3000’ ‘1’ ‘A7’ 04h
1 byte 2 bytes 1 byte 4 bytes 1 byte 2 bytes 1 byte
Note
Broadcasting
Broadcasting sends commands to all inverters connected to the network simultaneously. When
commands are sent from station ID 255, each inverter acts on the command regardless of the station
ID. However no response is issued for commands transmitted by broadcasting
7.3.6.1 Detailed Read Protocol
Read Request:
Reads successive n words from address XXXX.
ENQ Station ID CMD Address Number of Addresses SUM EOT
05h ‘01’–’FA’ ‘R’ ‘XXXX‘ ‘1’–‘8’ = n ‘XX’ 04h
1 byte 2 bytes 1 byte 4 bytes 1 byte 2 bytes 1 byte
Total bytes=12. Characters are displayed inside single quotation marks(‘).