5
PROFIBUS-DP Operating Characteristics
Parameter setting via PROFIBUS-DP
50
Manual – MOVI-PLC
®
basic DHP11B.. controller
5.3
Parameter setting via PROFIBUS-DP
In the PROFIBUS-DP system, the parameters are accessed via the 8 byte MOVILINK
®
parameter channel. This parameter channel offers extra parameter services in addition
to the conventional
read
and
write
services.
Structure of
the 8 byte
MOVILINK
®
parameter
channel
PROFIBUS-DP enables access to the MOVI-PLC
®
basic
DHP11B.. parameters via the
"parameter process data object" (PPO). This PPO is transmitted cyclically and in addi-
tion to the process data channel [2], contains a parameter channel [1], which can be
used to exchange acyclical parameter values.
The following table shows the structure of the 8 byte MOVILINK
®
parameter channel. Its
basic structure is as follows:
• One management byte
• One reserved byte
• Two index bytes
• Four data bytes
58377AXX
Fig. 12: Communication via PROFIBUS-DP
Byte 0
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
Byte 7
Manage-
ment
Reserved
Index high
Index low
MSB data
Data
Data
LSB data
Parameter index
4 byte data
X31
X32
X33
X30
X34
20
21
22
23
24
25
26
DHP11B
1
2
3
1
2
3
1
2
3
2
3
1
[1]
[2]
[2]
[1]
0
0
I
