ABB RETA-02, Руководство пользователя

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Communication
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User Specific Record Data
User Specific Record Data can be used for global parameter
access. This index is supported for compatibility reasons.
Header and frame structures
PROFINET IO uses DCE RPC (Distributed Computing
Environment Remote Procedure Call) protocol for acyclic read
and acyclic write services. IO controllers and supervisors will take
care of formulating most of the request frames. However, it is
possible that handling the PROFIdrive request and response
headers must be performed in the application logic. The acyclic
frame structure, headers and error codes are described further
below.
Table 13.Ethernet frame structure
Dest addr. and the Src addr. are the destination and the source
of the communication relationship. The addresses are in
hexadecimal format, e.g. 00-30-11-02-57-AD.
Ether type is 0x800 for non-real-time communication.
IP and UDP fields contain the IP address of the source and the
destination as well as the communication ports and length of the
message.
RPC contains for example the read or write service ID, interface
description and selected objects.
NDR request block describes the length of the following data
block. The response block also contains bytes ErrorCode ,
ErrorDecode , ErrorCode1 and ErrorCode2 for presenting the
status of the request.
Frames
Dest
addr. Src
addr. Ether
type IP
UDP
RPC NDR
Read or
Write
Data
Bytes 6 6 2 28 80 20 64 ...