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How do I use rtems_termios_bufsize?! No doc!



Hi all,

Finally i got this issues all solved (at least for now). I struggled a bit
to get the APBUART rtems driver working, i had to make a slight modification
to the driver so it could coexist with the console driver for the stdio
dedicated UART and figure out some undocumented stuff about the driver
manager initialization. The APBUART driver worked correctly and i see no
problems using the UART assigned to APBUART driver in full-duplex mode,
contrary to what happened to the console driver (console.c).


Best,
JM



On Mon, Sep 27, 2010 at 6:58 PM, Jo?o Rasta <freakforever at gmail.com> wrote:

> Hi all,
>
> Well i have been able to reproduce the problem. Instead of the previous
> host (dSPACE), i used a PC as a host and implemented a simple application to
> perform both reads and writes via the serial link to the FPGA board running
> rtems. The rtems software simply performs writes() to the serial line at a
> fixed rate. I saw that:
>
> 1) If the rtems running on the FPGA board only sends data to the host, it's
> OK.
>
> 2) Instead of only reading, if the host also writes, even if there are no
> read()'s at the rtems side which only keeps write()'ing, i start to loose
> bytes received at the host side.
>
> Since there are two independent Rx and Tx lines, i did not expect this to
> occur. Also, there are two separated hardware fifos for both Tx and Rx and
> since i have no read()'s on the rtems side i expect no software calls when
> bytes arrive, hence no software overheads.
>
> What am i missing?
>
>
> Best,
> JM
>
>
>
> On Fri, Sep 24, 2010 at 4:41 PM, Jo?o Rasta <freakforever at gmail.com>wrote:
>
>> In order to discard hardware issues I now tried the same application on a
>> more powerful FPGA. Here the leon-3 processor runs at 80MHz and UART
>> hardware fifos size are doubled to 32 bytes. However the problem is still
>> the same. Rx works well, the packets received are ok but the packets sent
>> are not correct.
>>
>> I suspect of a problem on the driver. If i set a big buffer, 1024 as chris
>> suggested, "trash" bytes are sent. This does not happen if i set a buffer
>> lower than the message i want to send but in this case i loose bytes.
>>
>> Termios is well configured, the simplest way possible. I'm using POSIX
>> rtems support.
>>
>> Can that warning on the driver be the problem? Transmissions in interrupt
>> mode not working well? Is there any other driver i can use?
>>
>>
>> Best,
>> JM
>>
>>
>>
>>
>> On Fri, Sep 24, 2010 at 3:25 PM, Jo?o Rasta <freakforever at gmail.com>wrote:
>>
>>> Sorry, it is this one:
>>>
>>> rtems-4.10-mingw\src\rtems-4.10\c\src\lib\libbsp\sparc\leon3\console
>>>
>>>
>>>
>>>
>>> On Fri, Sep 24, 2010 at 3:15 PM, Sebastian Huber <
>>> sebastian.huber at embedded-brains.de> wrote:
>>>
>>>> On 09/24/2010 04:04 PM, Jo?o Rasta wrote:
>>>> > The filename is console.c. I'm using rtems 4.10 from
>>>> >
>>>> > ftp://gaisler.com/gaisler.com/rcc/src/
>>>>
>>>> There are 48 console.c files in this archive.
>>>>
>>>> >
>>>> >
>>>> > Best,
>>>> > JM
>>>> >
>>>> > On Fri, Sep 24, 2010 at 1:13 PM, Sebastian Huber
>>>> > <sebastian.huber at embedded-brains.de
>>>> > <mailto:sebastian.huber at embedded-brains.de>> wrote:
>>>> >
>>>> >     On 09/24/2010 02:01 PM, Jo?o Rasta wrote:
>>>> >     > Hi,
>>>> >     >
>>>> >     > I have checked the termios configuration again, it seems ok. No
>>>> >     software
>>>> >     > flow control, no canonical mode. Also the same configuration
>>>> works
>>>> >     fine
>>>> >     > on a x86.
>>>> >     >
>>>> >     > I'm using gaisler's console driver and when i opened the rtems
>>>> driver
>>>> >     > file it said this:
>>>> >     [...]
>>>> >
>>>> >     What is the file name path of this file and the CVS version in
>>>> your
>>>> >     case?
>>>> >
>>>> >     --
>>>> >     Sebastian Huber, embedded brains GmbH
>>>> >
>>>> >     Address : Obere Lagerstr. 30, D-82178 Puchheim, Germany
>>>> >     Phone   : +49 89 18 90 80 79-6
>>>> >     Fax     : +49 89 18 90 80 79-9
>>>> >     E-Mail  : sebastian.huber at embedded-brains.de
>>>> >     <mailto:sebastian.huber at embedded-brains.de>
>>>> >     PGP     : Public key available on request.
>>>> >
>>>> >     Diese Nachricht ist keine gesch?ftliche Mitteilung im Sinne des
>>>> EHUG.
>>>> >     _______________________________________________
>>>> >     rtems-users mailing list
>>>> >     rtems-users at rtems.org <mailto:rtems-users at rtems.org>
>>>> >     http://www.rtems.org/mailman/listinfo/rtems-users
>>>> >
>>>> >
>>>>
>>>>
>>>> --
>>>> Sebastian Huber, embedded brains GmbH
>>>>
>>>> Address : Obere Lagerstr. 30, D-82178 Puchheim, Germany
>>>> Phone   : +49 89 18 90 80 79-6
>>>> Fax     : +49 89 18 90 80 79-9
>>>> E-Mail  : sebastian.huber at embedded-brains.de
>>>> PGP     : Public key available on request.
>>>>
>>>> Diese Nachricht ist keine gesch?ftliche Mitteilung im Sinne des EHUG.
>>>>
>>>
>>>
>>
>
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