Rockwell Automation 2098-DSD-xxx Ultra3000 Host Commands for Serial Interface - Manual (Page 15)

Publication 2098-RM003A-EN-P October 2001
Communications Protocol 1-3
The Parameter field of the response is the same as that of the
command, unless the drive is unable to execute the command, in
which case it returns an exception response. (Examples of exception
causes are invalid function number, illegal data, etc.). An exception
response is generated from the command parameter code by setting
the most significant bit of the parameter code field. (Equivalently, it is
generated by adding 0x800 to the command parameter code.)
The Function field of the response is the same as the command.
The Data field contains data requested from the drive, if any. If an
exception occurred, the data field is made up of two characters, which
identify the type of exception.
The Checksum field is generated in the same manner as in the host
command, with the sum of the Address, Parameter, Function, Data,
and Checksum field set equal to zero.
Exception Responses If a command is received by the drive without a communication error,
but cannot be processed normally, an exception response is
generated. The possible exception responses are as follows:
Response Data Exception Type Description
01 Invalid Data The command data parameter was
unacceptable, and the parameter was
not changed in the drive.
02 Command Not Enabled The command is disabled and is
dependent on another command for
enabling.
03 EEPROM Write Error The command required a write to
EEPROM, and the data could not be
written.
04 Data Below Minimum The command data was less than the
minimum value, and the parameter
was not changed in the drive.
05 Data Above Maximum The command data was greater than
the maximum value, and the
parameter was not changed in the
drive.
06 Command Disabled
When Drive is Enabled The command cannot be complied
with because the drive is enabled.
07 Invalid Array Index The array index is out of range.
08 Invalid Function Code The host function code was not
recognized by the drive.
09 Invalid Parameter
Number The host parameter number was not
recognized by the drive.