Danfoss VLT AutomationDrive FC 301 Series Design Manual page 202

RS-485 Installation and Set...
Register
number
00001-00006
00007
00008
00009
00010-00990
01000-01990
02000-02990
03000-03990
04000-04990
...
49000-49990
50000
50010
...
50200
50210
Table 12.16 Holding Registers
* Used to specify the index number to be used when accessing an
12 12
indexed parameter.
12.11.9 How to Control the Adjustable
Frequency Drive
This section describes codes which can be used in the
function and data fields of a Modbus RTU message.
200
Description
Reserved
Last error code from an FC data object interface
Reserved
Parameter index*
000 parameter group (parameters 001 through
099)
100 parameter group (parameters 100 through
199)
200 parameter group (parameters 200 through
299)
300 parameter group (parameters 300 through
399)
400 parameter group (parameters 400 through
499)
...
4900 parameter group (parameters 4900 through
4999)
Input data: Adjustable frequency drive control
word register (CTW).
Input data: Bus reference register (REF).
...
Output data: Adjustable frequency drive status
word register (STW).
Output data: Adjustable frequency drive main
actual value register (MAV).
Design Guide
12.11.10 Function Codes Supported by
Modbus RTU supports use of the following function codes
in the function field of a message.
Function
Read coils
Read holding registers
Write single coil
Write single register
Write multiple coils
Write multiple registers
Get comm. event counter
Report follower ID
Table 12.17 Function Codes
Function
Diagnostics
Table 12.18 Function Codes
12.11.11 Modbus Exception Codes
For a full explanation of the structure of an exception code
response, refer to chapter 12.11.5 Function Field.
Code Name
1 Illegal
function
Rev. 2014-04-04 All rights reserved.
Modbus RTU
Function code (hex)
1
3
5
6
F
10
B
11
Function Sub- Sub-function
Code function
code
8 1 Restart communication
2 Return diagnostic register
10 Clear counters and
diagnostic register
11 Return bus message count
12 Return bus communi-
cation error count
13 Return follower error
count
14 Return follower message
count
Meaning
The function code received in the query is
not an allowable action for the server (or
follower). This may be because the
function code is only applicable to newer
devices and was not implemented in the
unit selected. It could also indicate that
the server (or follower) is in the wrong
state to process a request of this type, for
example, because it is not configured and
is being asked to return register values.
MG33BF22