Danfoss VLT PROFIBUS DP MCA 101, Programming Manual

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set by the master within the corresponding
request telegram
•
A data field, where the requested data are placed.
If one or more internal requests have failed, an
error code is placed instead of the data values
DP-V1 Parameter response Byte no.
Response header Request ref. mirrored 0
Response ID 1
Axis mirrored 2
Parameter values No. of parameters 3
Format 4
No. of values 5
Values of error values 6
n'th parameter value ...
Table 5.7 DP-V1 Parameter Response Telegram
As the response telegram does not include parameter
addressing information, the master must identify the
structure of the response data from the request telegram.
5.2.9 Request/Response Attributes
Table 5.8 contains an overview of the possible attributes of
the PROFIdrive parameter channel.
Field Data
type
1)
Values Remark
Request
reference
U8 0x01..0xF
F
Request ID U8 0x01 Request parameter
value
Identification for
read or write
request
0x02 Change parameter
value
0x42 Change parameter
non-volatile
0x51 Request par. value
double word
0x52 Change par. value
double word
Response
ID
U8 0x01 Request parameter
(+) Positive
Identification for
the response
0x02 Change parameter
(+) Positive
0x81 Request parameter
(-) Negative
0x82 Change parameter (-)
Negative
Axis U8 0x00..0xF
F
Number (always 0)
No. of
parameter
s
U8 0x01..0x2
5
Limitation: DP-V1
telegram length
Attribute U8 0x10 Value
0x20 Description Data description
0x30 Text
No. of
elements
U8 Limitation: DP-V1
telegram length
0x01-0xF
A
Quantity 1-234
Parameter
no.
U16 0x0001... Number 1-65535 Parameter
number
0xFFFF
Subindex U16 0x0000 Number 0-65535 Array pointer
0xFFFF
Format U8 See table
No. of
values
U8 0x01..0xE
A
Quantity 0-234 Limitation: DP-V1
telegram length
Error no. U16 0x0000... Error number
Table 5.8 Overview: Possible Attributes of the
PROFIdrive Parameter Channel
1) U8 - Unsigned8, U16 - Unsigned16
5.2.10 Request Reference
Unique identification of request/response pair for the
master. The master changes the request reference with
each new request. The slave mirrors the request reference
in the response.
5.2.11 Request ID
0x01 Request parameter.
0x02 Change parameter (data is NOT stored in non-volatile memory,
lost at power cycle).
0x42 Change parameter non-volatile (data is stored in non-volatile
memory).
0x51 Request parameter value double word. All parameters are
formatted and transferred as double word size, regardless of the
actual data type.
0x52 Change parameter value double word. All parameters must be
formatted and sent as double word size, regardless of data type.
Table 5.9 Defined Request Identification
5.2.12 Response ID
The response ID indicates if the read or write request was
successfully performed in the frequency converter. If the
response is negative, the request is answered negative
(first bit=1) and an error code is entered per partial
response, instead of the value.
5.2.13 Axis
The axis attribute should be set to 0.
5.2.14 Number of Parameters
For multi-parameter requests specifying the number of the
parameter address and/or parameter value areas. For a
single request, the number is 1.
5.2.15 Attribute
The attribute determines which data to access. The
frequency converter responds to the attributes value (10
H), description (20 H) and text (30 H).
5.2.16 Attribute Value (10H)
The attribute value permits reading or writing of parameter
values.
Parameter Access Programming Guide
26 Danfoss A/S © Rev. 05/2014 All rights reserved. MG37G102
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