FC101 Design Guide

CTW
Holding
Register
2810
Write
Master Frequency Converter
Read
Frequency
Converter Master
Controlled by
Parameter
Holding
Register
Controlled by
Parameter
8-42 [0]
REF
2811
8-42 [1]
2812
8-42 [2]
PCD 2
write
2813
8-42 [3]
PCD 3
write
2814
8-42 [4]
PCD 4
write
2815
8-42 [5]
PCD 5
write
...
...
...
write
2873
8-42 [63]
PCD 63
write
STW
2910
8-43 [0]
MAV
2911
8-43 [1]
2912
8-43 [2]
PCD 2
read
2913
8-43 [3]
PCD 3
read
2914
8-43 [4]
PCD 4
read
2915
8-43 [5]
PCD 5
read
...
...
...
read
2919
8-43 [63]
PCD 63
read
130BC048.10
Figure 7.14 Accessing via PCD write/read
NOTICE!
The boxes marked in grey are not changeable, they are
default values.
NOTICE!
The 32 bit parameters must be mapped inside the 32 bit
boundaries (PCD2 & PCD3 or PCD4 & PCD5, and so on.),
where the parameter number is mapped twice to
parameter 8-42 PCD Write Conguration or
parameter 8-43 PCD Read Conguration.
7.8.10 How to Control the Frequency
Converter
This section describes codes which can be used in the
function and data elds of a Modbus RTU telegram.
7.8.11 Function Codes Supported by
Modbus RTU
Modbus RTU supports use of the following function codes
in the function eld of a telegram.
Function Function code (hex)
Read coils 1
Read holding registers 3
Write single coil 5
Write single register 6
Write multiple coils F
Write multiple registers 10
Get comm. event counter B
Report slave ID 11
Read write multiple registers 17
Table 7.19 Function Codes
Function
Function
code
Subfunction
code
Subfunction
Diagnostics 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 slave error count.
14
Return slave message
count.
Table 7.20 Function Codes
7.8.12 Modbus Exception Codes
For a full explanation of the structure of an exception code
response, refer to chapter 7.8.5 Function Field.
Code Name Meaning
1
Illegal
function
The function code received in the query is
not an allowable action for the server (or
slave). 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 slave) is in the wrong state to
process a request of this type, for example
because it is not congured and is being
asked to return register values.
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