Modbus message, 3 exception codes (ec) – Lenze ESVZAR0 RS-485 User Manual
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CMVMB401C
Modbus Message
6.2
Register Writing
6.2.1 Message structure for reading one word
All writable registers
W
SA
06
RH
RL
DH
DL
CRCH
CRCL
RS
SA
06
RH
RL
DH
DL
CRCH
CRCL
6.3
No Response Conditions
The drive will not respond to any message that:
• contains one or more parity errors
• has an invalid CRC value
• was not directed to the drive’s network address.
• This drive does not support the broadcast function of the Modbus protocol.
• is not at least 8 bytes long (minimum required for the supported functions)
• is more than 18 bytes long (maximum allowed before input buffer overflow occurs)
6.4
Exception Responses
If a valid message is received (i.e. parity, crc, address and message length all pass validity checks), but the message
contents are somehow invalid, the drive will respond with a Modbus exception.
6.4.1 Message structure for an exception response to a read request (03)
W
SA
83
EC
CRCH
CRCL
6.4.2 Message structure for an exception response to a write request (06)
W
SA
86
EC
CRCH
CRCL
6.4.3 Exception Codes (EC)
EC
Description
01
Command rejected; Illegal function
02
Invalid register number
03
Data value is out-of-range
04
Wrong data format
06
Slave device (drive) busy