Re: ttyUSB sendbreak problem

[Thiago Galesi <thiagogalesi@gmail.com>]

And in this case BREAK is which character?? 0x00?

Anyway, take a look at the stty options and man termios (even though
they may do what your IOCTL is doing)

Also explain what's happening exactly: what does "but
> fails using USB to serial adapters" mean.




On Mon, Feb 16, 2009 at 8:29 PM, Jean-Denis Girard <jd.girard@sysnux.pf> wrote:
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> Hi list,
>
> I'm writing a program which communicates via modem with an embedded
> device (electrical network monitoring). The frames are terminated by a
> BREAK.
>
> My program works fine when I use a Cyclades 8Yo multiports card, but
> fails using USB to serial adapters (tried with pl2303 and FTDI
> converters). I suspect that the BREAK are not passed correctly, but I
> don't have equipment to check.
>
> I've tried with:
>  tcsendbreak(modem,0);
>  ioctl(modem, TCSBRK,0);
>  ioctl(modem, TCSBRKP, 0);
>
> - From pl2303 debug mode, I see that pl2303_break_ctl is called:
>  drivers/usb/serial/pl2303.c: pl2303_break_ctl - port 0
>  drivers/usb/serial/pl2303.c: pl2303_break_ctl - turning break on
>  drivers/usb/serial/pl2303.c: pl2303_write_bulk_callback - port 0
>  drivers/usb/serial/pl2303.c: pl2303_send - port 0
>  drivers/usb/serial/pl2303.c: pl2303_break_ctl - port 0
>  drivers/usb/serial/pl2303.c: pl2303_break_ctl - turning break off
>
> I found a few references of similar problems in the past, but it was for
> older kernels (I'm using 2.6.28.4), so the question remains: should it
> work or is there a known problem sending BREAK using ttyUSB?
>
>
> Thanks,
> - --
> Jean-Denis Girard
>
> SysNux                  Systèmes  Linux  en Polynésie française
> http://www.sysnux.pf/   Tél: +689 50 10 40 / GSM: +689 79 75 27
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-- 
-
Thiago Galesi