Re: a problem with serial port (can't post in mail-list)

["Joel Sherrill <joel at OARcorp dot com>" <joel dot sherrill at OARcorp dot com>]

I received this personally and am forwarding it to the list.

I sent David info on why he might not have been able to post.

--joel

David García wrote:
> Hi, I've tried to post my doubt in the rtems-users@rtems.com 
> <mailto:rtems-users@rtems.com> mailing list but I'm not really sure if 
> it has been send correctly as there was no feedback and my post doesn't 
> appear in the website.
>
> Is for that I'm writting to you directly becaus I'm having some problems 
> with rtems, and I explain it below:
>
> We are trying to do a migration from a Linux application to RTEMS v4.6 
> using the pc386 BSP. The application runs well under Linux but under 
> RTEMS does not run well.
>
> The cross compiler does not report an error but at runtime the code hangs.
>
> We think the code hangs when we do the following call to ioctl:
>
> "ioctl(fdes, FIONREAD, (int)&unread)"
>
> - fdes is the file descriptor that we have obtained by opening the 
> serial port COM1, which is registered in the system with the name 
> "/dev/ttyS1". Since the function open "/dev/ttyS1",O_RDWR | O_NONBLOCK | 
> O_NOCTTY) does not result in an error we assume that the drivers have 
> been initialized correctly. We used the TT1_DRIVER_TABLE_ENTRY, defined 
> in the file tty_drv.h, to add the appropriate entry to the device driver 
> table of the RTEMS configuration.
>
> - (int)&unread is the pointer to an integer were we want to obtain the 
> unread bytes.
>
> We have seen that FIONREAD definition in ioccom.h differs from the one 
> that is defined in the ioctls.h header of linux libraries.
>
> We suspect that is when we call the function ioctl that the application 
> fails, and the systems hangs up.
>
> The question is: should we do the ioctl call differently? Or could the 
> problem be in a different point of the application?
>
> Any sugestion will be wellcome.
>
> If you would like more information please do not hesitate to email back.
>
> Thank you very much for your patience.
>
> Best regards
>
> ------------------------------------------------------------------------
>
> David García Antón
>
> headhunternx@hotmail.com


--
Joel Sherrill, Ph.D.             Director of Research & Development
joel@OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
   Support Available             (256) 722-9985