Dear Peter
in order to control a Comau robot
I need to use the RTnet and RTAI libraries for the
real time communication with the robot controller.
The functioning is the following:
1) the external pc performs a blocking receiving on a previously opened socket
2) the robot controller sends a packet to the external pc
3) the pc receives the packet, performs proper calculations of the new
command
references and send bck the data to the controller
4) goto point 1.

It is important to highlight that the timing is decided by the robot
controller. In particular, the controller
sent the data to the pc every 2ms, and the pc has to answer after 1.4ms after
having received the packet.
In the case packet is lost, or the pc does not answer back in the proper
time,
the robot controller enters in a faulty state (it has to be restarted).

My idea is to implement in a Orocos component the thread which performs
the send and receive functionalities and writes on a "Data Flow Port" the
received information
for the other components. In your opinion, is it possible to realize this
kind of architecture?
Have you better ideas?

Thanks in advance for your help
Diego
>
>>----Messaggio originale----
>>Da: peter [..] ...
>>Data: 14/01/2013 23.38
>>A: "dgerb [..] ..."<dgerb [..] ...>
>>Cc: "Orocos Developers"<orocos-dev [..] ...>
>>Ogg: Re: Re: [Orocos-Dev] (no subject)
>>
>>On Mon, Jan 14, 2013 at 12:13 PM, dgerb [..] ... <dgerb [..] ...> wrote:
>>> the output of gdb ./main-test
>>>
>>> Reading symbols from
>>> /home/laboratorio/orocos/orocos-toolchain/rtt/build/tests/main-test...
done.
>>>
>>> (gdb) run
>>>
>>> Starting program:
>>> /home/laboratorio/orocos/orocos-toolchain/rtt/build/tests/main-test
>>>
>>> [Thread debugging using libthread_db enabled]
>>>
>>>
>>> Program terminated with signal SIGKILL, Killed.
>>
>>Hmm, that's right, you can't debug a kernel oops with GDB.
>>
>>I can't provide further help in debugging this without having an RTAI
>>system of my own.
>>
>>It's likely that there has been a change in RTAI how it handles the
>>LXRT calls, and that we still rely on older data structures.
>>
>>You could test this with turning the cmake option OS_AGNOSTIC off:
>>
>>cd rtt/build
>>cmake .. -DOS_AGNOSTIC=OFF
>>make check
>>
>>It's worth a try...although I can't predict how well all will build,
>>it could be that you have to add extra RTAI include paths here and
>>there in order to find the rtai_[...].h header files, especially when
>>building components.
>>
>>Peter
>>
>