Operating instructions

5.3.3. Request / Response Handling
The RC portion of the PCA word defines the requests that may be issued from the master to the
slave as well as what other portions of the PCV (IND and PVA) are involved. The PVA portion will
transmit word-size parameter values in bytes 7 and 8, while long word size values require bytes
5 to 8 (32 bits). If the Response / Request contains array elements, the IND will carry the Array
Sub-index. If parameter descriptions are involved, the IND will hold the Record Sub-index of the
parameter description.
5.3.4. RC Content
Request Function
0 No request
1 Request parameter value
2 Change parameter value (word)
3 Change parameter value (long
word)
4 Request description element
5 Change description element
6 Request parameter value (array)
7 Request parameter value (array
word)
8 Request parameter value (array long
word)
9 Request number of array elements
10-15 Not used
If the slave rejects a request from the master,
the RC word in the PPO-read will indicate this
by assuming the value 7. The fault number will
be carried by bytes 7 and 8 in the PVA ele-
ment.
Re-
sponse
Function
0 No response
1 Transfer parameter value (word)
2 Transfer parameter value (long
word)
3 Transfer description element
4 Transfer parameter value (array
word)
5 Transfer parameter value (array long
word)
6 Transfer number of array elements
7 Request rejected (incl. fault #, see
below)
8 Not serviceable by PCV interface
9 Not used
10 Not used
11 Not used
12 Not used
13-15 Not used
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