Siemens SIPROTEC PROFINET IO User Manual

2 PROFINET IO in SIPROTEC
2.8 Acyclic Reading and Writing of Data
46 SIPROTEC 4, Communication Module PROFINET IO, Communication Profile
C53000-L1840-C360-1, Edition 08.2012
2.8 Acyclic Reading and Writing of Data
2.8.1 Presetting and Resetting Metered Values and Statistic Values
An acyclic write telegram is defined for presetting and resetting the metered values and statistic values.
Depending on the definition of the IO module, up to 8 values can be set with this telegram. The order of the
values in the telegram corresponds to the order of the values in the IO module, see Chapter 2.4. A masking
byte allows selecting the values to be set.
Figure 2-22 Acyclic Data Telegram, Presetting and Resetting Metered Values and Statistic Values
Number of Values
• IO module for metered values: 4
• IO module for statistic values: 3 or 6
Masking Byte
Each bit in this byte corresponds to one value in the telegram. The associated value is only evaluated in the
device if the masking bit is set. Unused masking bits must
be set to zero.
Value #1 through Value #8
Depending on the data type, the values to be set are transmitted at the respective telegram positions as Unit32
for metered values or as Float32 for statistic values. The telegram always only contains as many value entries
as entered in the byte "Number of values".
Siemens recommends setting unused values to zero, for example values for which no masking bit is set.
Number of values
Masking byte
Value #1 in the IO module
(Ulong32 or Float32)
Value #8 in the IO module
(Ulong32 or Float32)
Byte offset = 0
Byte offset = 2
Start offset = 4
Start offset = 8
Start offset = 32
Max. end offset = 35
...
Reserved = 0
Reserved = 0
Byte offset = 1
Byte offset = 3
Masking byte
7 6 5 4 3 2 1 0
Bit position
Meaning
Value setting #8 Value setting #7 Value setting #6 Value setting #5 Value setting #4 Value setting #3 Value setting #2 Value setting #1
NOTE
For statistic values:
The EN100 rejects invalid Float32 values (Not a Number values) and does not take over such values.
com_profinet-io_profile_us.book Page 46 Friday, August 17, 2012 1:40 PM

Siemens SIPROTEC PROFINET IO Specifications

General

Brand	Siemens
Model	SIPROTEC PROFINET IO
Category	Control Unit
Language	English