4 Commissioning
4.12 Acyclic data
DX-NET-PROFINET2-2
01/22 MN040062EN
www.eaton.com
87
4.12.4.2 PROFINET write request
Write request - read job
Only individual parameter reading is supported (i.e., array and multiple para-
meter reading is not supported). The telegram length of the parameter
request is set at 10 bytes.
Various objects can be transmitted in the parameter channel – these objects
are identified by what is referred to as a PNU (parameter number) and a sub-
index. The write request includes a declaration that specifies that the job is a
read job.
Table 46:
Write request
Byte
Designation
Description
0
Request Reference
Request identification
Unique identification for a request/response pair for the master.
The master can increment the identification number for each new
request in the application.
They are then mirrored by variable frequency drive/variable speed
starter.
01
hex
- FF
hex
(i.e. 1
dec
- 255
dec
)
1
Request ID
Request ID
The type of request is specified here.
01
hex
: Read job
2
DO-ID
Drive-Object-ID
00
hex
3
No. of Paramters
Number of parameters
Only individual parameter processing is supported.
01
hex
.
4
Attribute
Attribute
Defines which object type should be accessed.
10
hex
(16
dec
): Value
5
No. of Elements
Number of elements
Number of vector elements or length of the string being accessed.
PNU 0 up to PNU 999: 00hex (only for subindex 0)
PNU 0 to PNU 999 (without 202): 01
hex
6, 7
Parameter number
Parameter number (PNU)
Address of the parameter that should be accessed
0000
hex
- FFFF
hex
(i.e. 0
dec
- 65535
dec
)
8, 9
Subindex
Subindex
Address of the parameter's first field element or start of the text
0000
hex
- FFFF
hex
(i.e. 0
dec
- 65535
dec
)
