Goodrive350A series high-performance multifunction VFD
Communication
-333-
Code
Name
Description
09H
Password
protection
A user password is set, and the upper computer does not provide the
password to unlock the system when performing a read or write
operation. The error of "system locked" is reported.
When returning a response, the slave device uses a function code domain and fault address to
indicate whether it is a normal response (no error) or exception response (some errors occur). In a
normal response, the device returns the corresponding function code and data address or
sub-function code. In an exception response, the device returns a code that is equal to a normal code,
but the first bit is logic 1.
For example, if the master device transmits a request message to a slave device for reading a group
of function code address data, the code is generated as follows:
0 0 0 0 0 0 1 1 (03H in the hexadecimal form)
For an exception response, the following code is returned:
1 0 0 0 0 0 1 1 (83H in the hexadecimal form)
In addition to the modification of the code, the slave device returns a byte of exception code that
describes the cause of the exception. After receiving the exception response, the typical processing
of the master device is to transmit the request message again or modify the command based on the
fault information.
For example, to set the "Channel of running commands" (P00.01, the parameter address is 0001H) of
the VFD whose address is 01H to 03, the command is as follows:
VFD
address
Write
command
Parameter
address
Parameter
data
CRC
01
06
00 01
00 03
98 0B
However, the setting range of the "Running command channel" is 0 to 2. The value 3 exceeds the
setting range. In this case, the VFD returns an error message response as shown in the following:
VFD
address
CRC
Error code
Exception
response code
01
86
04
43 A3
The exception response code 86H (generated based on the highest-order bit "1" of the write
command 06H) indicates that it is an exception response to the write command (06H). The error code
is 04H. From the preceding table, we can see that it indicates the error "Operation failure", which
means "The parameter is set to an invalid value in the write operation".
9.4.8 Read/Write operation example
For details about the formats of the read and write commands, see sections 9.4.1 and 9.4.2.
