Specifications

7.4.7 The PKE Field
The PKE field contains 2 subfields: Parameter command
and response (AK) and Parameter number (PNU):
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
130BB918.10
PKE IND
PWE
high
PWE
low
AK PNU
Parameter
commands and replies
Parameter number
Illustration 7.8 PKE Field
Bits no. 12-15 transfer parameter commands from master
to follower and return processed follower responses to the
master.
Parameter commands master ⇒ follower
Bit no. Parameter command
15 14 13 12
0 0 0 0 No command
0 0 0 1 Read parameter value
0 0 1 0 Write parameter value in RAM (word)
0 0 1 1 Write parameter value in RAM (double
word)
1 1 0 1 Write parameter value in RAM and
EEprom (double word)
1 1 1 0 Write parameter value in RAM and
EEprom (word)
1 1 1 1 Read text
Table 7.5 Parameter Commands
Response follower ⇒ master
Bit no. Response
15 14 13 12
0 0 0 0 No response
0 0 0 1 Parameter value transferred (word)
0 0 1 0 Parameter value transferred (double
word)
0 1 1 1 Command cannot be performed
1 1 1 1 text transferred
Table 7.6 Response
If the command cannot be performed, the follower sends
this response:
0111 Command cannot be performed
- and issues the following fault report in the parameter
value:
Error code FC+ Specification
0 Illegal Parameter Number
1 Parameter cannot be changed.
2 Upper or lower limit exceeded
3 Subindex corrupted
4 No Array
5 Wrong Data Type
6 Not used
7 Not used
9 Description element not available
11 No parameter write access
15 No text available
17 Not while Running
18 Other error
100
>100
130 No bus access for this parameter
131 Write to factory set-up not possible
132 No LCP access
252 Unknown viewer
253 Request not supported
254 Unknown attribute
255 No error
Table 7.7 Follower Report
7.4.8
Parameter Number (PNU)
Bits no. 0-11 transfer parameter numbers. The function of
the relevant parameter is defined in the parameter
description in 6 How to Programme.
7.4.9
Index (IND)
The index is used with the parameter number to read/
write-access parameters with an index, for example,
15-30 Alarm Log: Error Code. The index consists of 2 bytes;
a low byte, and a high byte.
Only the low byte is used as an index.
7.4.10
Parameter Value (PWE)
The parameter value block consists of 2 words (4 bytes),
and the value depends on the defined command (AK). The
master prompts for a parameter value when the PWE block
contains no value. To change a parameter value (write),
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HVAC Basic Drive FC 101 Design Guide
84 MG18C502 - Rev. 2013-09-06
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