bkinnightskytw
/
ethercat
mirror of https://gitlab.com/bkinnightskytw/ethercat.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

VoE handlers.

This commit is contained in:
Florian Pose 2008-10-22 11:53:40 +00:00
parent 0e6c64b8ea
commit 0fc0b5a0ae
1 changed files with 31 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
documentation/ethercat_doc.tex
View File

@ -571,7 +571,6 @@ physical memory to logical process data images.
% Pdo entry registration
% Sdo configuration
% Sdo access
% VoE handlers
The application interface provides functions and data structures for
applications to access an EtherCAT master. The complete documentation of the
@ -710,6 +709,35 @@ frames.
%------------------------------------------------------------------------------
\section{VoE Handlers}
\label{sec:api-voe}
During the configuration phase, the application can create handlers for the
VoE mailbox protocol described in sec.~\ref{sec:voe}. One VoE handler always
belongs to a certain slave configuration, so the creation function is a method
of the slave configuration.
A VoE handler manages the VoE data and the datagram used to transmit and
receive VoE messages. Is contains the state machine necessary to transfer VoE
messages.
The VoE state machine can only process one operation at a time. As a result,
either a read or write operation may be issued at a time\footnote{If
simultaneous sending and receiving is desired, two VoE handlers can be created
for the slave configuration.}. After the operation is initiated, the handler
must be executed cyclically until it is finished. After that, the results of
the operation can be retrieved.
A VoE handler has an own datagram structure, that is marked for exchange after
each execution step. So the application can decide, how many handlers to
execute before sending the corresponding EtherCAT frame(s).
For more information about the use of VoE handlers see the documentation of
the application interface functions and the example applications provided in
the \textit{examples/} directory.
%------------------------------------------------------------------------------
\section{Concurrent Master Access}
\label{sec:concurr}
\index{Concurrency}
@ -1969,17 +1997,9 @@ constraints regarding this protocol.
The EtherCAT master allows to create multiple VoE handlers per slave
configuration via the application interface (see chap.~\ref{chap:api}). These
handlers contain the state machine necessary for the communication via VoE.
One read or write operation may be issued at a time. After the operation is
initiated, the handler must be executed cyclically until it is finished. After
that, the results of the operation can be retrieved.
A VoE handler has an own datagram structure, that is marked for exchange after
each execution step. So the application can decide, how many handlers to
execute before sending the corresponding EtherCAT frame(s).
For more information about using VoE handlers, see the application interface
documentation (chap.~\ref{chap:api}) or the example applications provided in
the \textit{examples/} subdirectory.
For more information about using VoE handlers, see sec.~\ref{sec:api-voe} or
the example applications provided in the \textit{examples/} subdirectory.
%------------------------------------------------------------------------------