09.02 Start-Up
Siemens AG 6SE7087-6AK85-1AA0
4-65
Rectifier/Regenerating Unit Operating Instructions
Structure of a telegram for PKW data exchange:
The telegram consists of the following data words:
Identifier
ID
Parameter identifier
PKE
Parameter index
IND
Parameter value 1
PWE1
Parameter value 2
PWE2
ID is the CAN identifier that is defined for the COB in question by parameterization.
PKE contains the request or response ID and the parameter number
Request or response ID Parameter number
PNU
Bit 0 to bit 10 contain the number of the parameter concerned. Bit 12 to bit 15 contain the request or
response ID.
The index
IND contains the value 0 for unindexed parameters, for indexed parameters it contains the
corresponding index value. Bit15 also has a special function as the page select bit for parameter
numbers greater than 1999.
The index value 255 means that the request concerns all indices of the parameter in question. For a
change request, the parameter values must then be passed on for all indices of the parameter. Because
a COB can only contain up to 4 data words (8 bytes) of net data, use of this request is only possible for
parameters with (up to ) 2 indices. In the other direction, the drive supplies all index values in the
response telegram to a read request.
Details about the telegram structure can be found in Section 4.5.6, "Structure of request/response
telegrams“.
Example of a PKW request
:
Changing the parameter value of the indexed parameter P140.02 (in the RAM) to 5.000Ω.
The example telegram therefore contains the following values:
Request identifier 300
d
012C
h
for use of the IDs of the example above
Request code 7
d
7
h
"Change parameter value (array word)"
Parameter number 140
d
008C
h
=> PKE = 708C
h
Index 2
d
0002
h
Parameter value 5000
d
1388
h
3 decimal places (value = 5000)
Using the CAN BusAnalyser++ from Steinbeis, the transmit data appear as follows (data field length = 8
bytes, low and high bytes are shown swapped round):
Identifier Data field
2C 01 8C 70 02 00 88 13 00 00
ID PKE IND PWE1
The following transfer function is also available:
PKW Request Broadcast
A parameter job (request) is processed simultaneously by all slaves on the bus. The node address is not
used to generate the CAN identifier because this must be set identically on all slaves utilizing the PKW
Request Broadcast function. This common identifier is set in CB parameter 9 (P704). The corresponding
parameter response is made with the CAN identifier for PKW Response described above
Notes regarding PKW transmission:
The length of the job and the response is always 4 words. Jobs which apply to all indices of a parameter
(e.g. "Request all indices") are not possible.
As a general rule, the low-order byte (in words) or the low-order word (in double words) is transferred
first. SIMOVERT 6SE70 does not use double word parameters itself, these jobs can only be executed
where access is available to technology board parameters (e.g. T400).
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