Danfoss VLT PROFIBUS DP MCA 101 Programming Manual page 28

Parameter Access
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
Response header
Parameter values
5 5
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
Request U8
reference
Request ID U8
Response U8
ID
Axis U8
No. of U8
parameter
s
Attribute U8
No. of U8
elements
Parameter U16
no.
Subindex U16
Format U8
No. of U8
values
Error no. U16
Table 5.8 Overview: Possible Attributes of the
26
Parameter response
Request ref. mirrored
Response ID
Axis mirrored
No. of parameters
Format
No. of values
Values of error values
n'th parameter value
Values
1)
0x01..0xF
F
0x01 Request parameter
value
0x02 Change parameter
value
0x42 Change parameter
non-volatile
0x51 Request par. value
double word
0x52 Change par. value
double word
0x01 Request parameter
(+) Positive
0x02 Change parameter
(+) Positive
0x81 Request parameter
(-) Negative
0x82 Change parameter (-)
Negative
0x00..0xF Number (always 0)
F
0x01..0x2
5
0x10 Value
0x20 Description
0x30 Text
0x01-0xF Quantity 1-234
A
0x0001... Number 1-65535
0xFFFF
0x0000 Number 0-65535
0xFFFF
See table
0x01..0xE Quantity 0-234
A
0x0000... Error number
Danfoss A/S © Rev. 05/2014 All rights reserved.
Programming Guide
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
Byte no.
each new request. The slave mirrors the request reference
0
1
in the response.
2
3
5.2.11 Request ID
4
5
6
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
Remark
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
Identification for
response, instead of the value.
read or write
request
5.2.13 Axis
The axis attribute should be set to 0.
5.2.14 Number of Parameters
Identification for
the response
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
Limitation: DP-V1
telegram length
The attribute determines which data to access. The
frequency converter responds to the attributes value (10
H), description (20 H) and text (30 H).
Data description
Limitation: DP-V1
5.2.16 Attribute Value (10H)
telegram length
Parameter
The attribute value permits reading or writing of parameter
number
values.
Array pointer
Limitation: DP-V1
telegram length
MG37G102