Danfoss VLT PROFIBUS DP MCA 101 Programming Manual page 29

Parameter Access
Master Slave SAP Description
SAP
50 (32H) 49 (31H) Master Class 2: Initiate request
50 (32H) 0..48 (0..30H) Master Class 2: Abort, read, write,
data transfer
51 (33H) 50, 51 (32H, Master Class 2: Alarm
33H)
51 (33H) 51 (33H) Master Class 2: Read, write
Table 5.2 Service Access Points (SAP)
5.2.6 DP-V1 Features for Parameter Access
This section describes how to use DP-V1 for accessing
frequency converter parameters.
The standard PROFIBUS DP-V1 read and write services are
not sufficient for accessing the many parameters and
attributes in the frequency converter. For this reason, the
PROFIdrive parameter channel is defined. Using this
parameter read/write is performed by addressing a single
DP-V1 object in the frequency converter as shown in the
example, Table 5.3.
For a detailed description of the DP-V1 command handling,
refer to the PROFIBUS DP-V1 Design Guide.
Example
Slot=0
Index=47
PROFIBUS Data unit
telegram
DP-V1
header
command/response
DU DU DU DU
0 1 2 3
Table 5.3 General Structure for Telegram
Use the DP-V1 command/response part for the standard
DP-V1 read/write on slot 0, index 47 data block.
Use the PROFIdrive V3 parameter channel to access specific
parameter data in the frequency converter.
MG37G202
Programming Guide
PROFIBUS
telegram
PROFIdrive V3.0
trailer
parameter
channel
Req./Res. Data
Header
Danfoss A/S © 01/2016 All rights reserved.
5.2.7 DP-V1 Read/Write Services
Table 5.4 shows the content of the DP-V1 command/
response headers and their possible attributes.
DU byte Value Meaning
0 Function Idle REQ, RES
number
0x48
0x51 Data transport
REQ, RES
0x56 Resource manager
REQ
0x57 Initiate REQ, RES
0x58 Abort REQ
0x5C Alarm REQ, RES
0x5E Read REQ, RES
0x5F Write REQ, RES
0xD1 Data transport
negative response
0xD7 Initiate negative
response
0xDC Alarm negative
response
0xDE Read negative
response
0xDF Write negative
response
1 Always zero Slot number
2 47 Index
3 xx Data length
4..n User data
Table 5.4 DP-V1 Command/Response Headers
5.2.8 DP-V1 Acyclic Parameter Channel
Use the PROFIdrive parameter channel for read and write
access to parameter values and attributes.
•
Parameter values of simple variable, array, and
visible string.
•
Parameter description elements such as type and
minimum/maximum value.
•
Descriptive text for parameter values.
•
Access to multiple parameters in 1 telegram is
also possible.
Table 5.5 shows the structure of the PROFIdrive parameter
channel.
Specified
–
–
5
–
–
–
–
–
–
–
–
–
–
–
DP-V1
DP-V1
DP-V1
PNO drive profile
V3.0
27
5