Rockwell Automation 22B PowerFlex 40 Custom Firmware Inst. - Option AF - Manual (Page 2)

Table A Response PDU
Table B Error PDU
Examples
Writing Drive Parameters
Write Parameters 38 through 40
• Parameter P038 [Speed Reference] = 3, “4-20mA Input”
• Parameter P039 [Accel Time 1] = 5.0 Sec
• Parameter P040 [Decel Time 1] = 15.0 Sec
Writing Control Registers
In the PowerFlex 40 drive the logic command can be accessed at address
0x2000 and the frequency reference can be accessed at address 0x2001.
These addresses can be written sequentially using Modbus function 16
(0x10). To set the following values:
• Logic Command = 0x1234
• RS485 Frequency Reference = 57.3 Hz
Field Name Length Range
Function Code 1 Byte 0x10
Starting Address 2 Bytes 0x0000 to 0xFFFF
Quantity of Registers 2 Bytes 1 to 123 (0x7B)
Field Name Length Range
Error Code 1 Byte 0x90
Exception Code 1 Byte 0x01 through 0x04
Request Response
Field Name (Hex) Field Name (Hex)
Function 10 Function 10
Starting Address Hi 00 Starting Address Hi 00
Starting Address Lo 26 Starting Address Lo 26
Quantity of Registers Hi 00 Quantity of Registers Hi 00
Quantity of Registers Lo 03 Quantity of Registers Lo 03
Byte Count 06
Registers Value Hi 00
Registers Value Lo 03
Registers Value Hi 00
Registers Value Lo 32
Registers Value hi 00
Registers Value Lo 96
Important: For bit descriptions, see Writing (06) Logic Command Data
in Appendix C of the PowerFlex 40 User Manual.
Error Responses
Table A Exception Code Table
If an attempt is made to write a sequence of parameters that includes
non-writeable parameters, the message will continue to write all writable
values, but will return an error code. If any of the parameters in the
sequence is read only, or run write inhibited, an error code of “4” will be
returned. If the value to be written is out of range or some other illegal
value, an error code of “3” will be returned. The returned error code does
not identify which of the parameters were not written.
Only a maximum of four control registers can be written beginning at
address 0x2000. If the starting address of the message is 0x2000 then the
length of the message must be 4 or less. If the starting register range and
the size of the intended write will reach beyond register 0x2003, an error
code of “2” will be returned and values will not be written to any of the
intended registers.
Request Response
Field Name (Hex) Field Name (Hex)
Function 10 Function 10
Starting Address Hi 20 Starting Address Hi 20
Starting Address Lo 00 Starting Address Lo 00
Quantity of Registers Hi 00 Quantity of Registers Hi 00
Quantity of Registers Lo 02 Quantity of Registers Lo 02
Byte Count 04
Registers Value hi 12
Registers Value Lo 34
Registers Value hi 02
Registers Value Lo 3D
Code Meaning
1 Illegal Function Code: The function code received in the query message is not
available for the receiving device.
2 Illegal Data Address: The data address received in the query message is not
available for the receiving device.
3 Illegal Data Value: The data value received in the query message is not
available for the receiving device.
4 Service Failure: The receiving device is unable to perform the requested action.
PowerFlex 70 Custom Firmware 3 2 PowerFlex 70 Custom Firmware