Danfoss VLT PROFIBUS DP MCA 101, Programming Manual

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5.2.20 Supported data types
Value Data type
3 Integer16
4 Integer32
5 Unsigned8
6 Unsigned16
7 Unsigned32
9 Visible string
10 Octet string (byte string)
33 N2 (standardised value)
35 V2 (bit sequence)
44 Error
54 Time difference without date indication
Table 5.12 Supported Data Types
5.2.21 Value
The value field contains the parameter value of the
request. When the response is negative, the field contains
a corresponding error code. If the values consist of an odd
number of bytes, a zero byte is appended to maintain the
word structure of the telegrams.
For a positive partial response, the parameter value field
contains the following attributes:
Format=Data type or byte, word, double word
Number of values=Actual number of values
Value=Parameter value
For a negative partial response, the parameter value field
contains the following:
Format=Error (44H)
Number of values=1
Value=Error value=Error number
5.2.22 Error Codes for Drive Profile V3.0
When the parameter request is invalid, the frequency
converter returns a corresponding error code.
Table 5.13
lists the full range of error codes.
Error
code
Meaning Additional
Info
0x00 Unknown parameter 0
0x01 Parameter is read-only. sub-index
0x02 Value out of range due to maximum/minimum
value.
sub-index
0x03 Wrong sub-index sub-index
0x04 Parameter is no array. 0
0x05 Wrong data type (wrong data length) 0
0x06 This parameter may not be set, only reset. sub-index
0x07 Descriptive element is read-only. sub-index
0x09 No description available (only value). 0
0x0b Process control not possible. 0
0x0f No text array available (only value). 0
0x11 Not possible in current state. 0
0x14 Value out of range due to drive state/configu-
ration.
sub-index
0x15 Reply too long (more than 240 bytes). 0
Error
code
Meaning Additional
Info
0x16 Wrong parameter address (unknown or
unsupported value for attribute, element,
parameter number or sub-index or illegal
combination)
0
0x17 Illegal format (for writing) 0
0x18 Value amount not consistent 0
0x65 Wrong axis: action not possible with this axis -
0x66 Unknown service request -
0x67 This service is not possible with multi parameter
access
-
0x68 Parameter value can not be read from bus. -
Table 5.13 Error Codes for DP-V1 Parameter Requests
5.3 PCV Parameter Access
The PROFINET cyclical data exchange performs parameter
access via the PCV channel. The PCV channel forms part of
the PPOs described in
chapter 4 Control .
Use the PCV channel to read and write parameter values,
and read status for descriptive attributes of each
parameter.
5.3.1 PCA Handling
The PCA part of PPO types 1, 2 and 5 performs several
tasks. Using PCA, the master controls and supervises
parameters, and requests a response from the follower.
Then the follower responds to a request from the master.
Requests and responses is a handshake procedure and
cannot be batched. Therefore, when the master sends out
a read/write request, it must wait for the response before
it sends a new request. The request or response data value
is limited to maximum 4 bytes (see RC characteristics in
Table 5.14 ), which implies that text strings are not
transferable. For further information, see
chapter 7 Application Examples .
5.3.2 PCA - Parameter Characteristics
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RC SMP PNU
Table 5.14 PCA - Parameter Characteristics
RC: Request/response characteristics (Range 0..15)
SMP: Spontaneous message (Not supported)
PNU : Parameter no. (Range 1..1999)
5.3.3 Request/Response Handling
The RC portion of the PCA word defines:
•
The requests issued from the master to the
follower.
•
Other portions of the PCV involved:
Parameter Access Programming Guide
28 Danfoss A/S © Rev. 05/2014 All rights reserved. MG37G102
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