Groups > comp.os.linux.development.apps > #163

Re: termios

From	Grant Edwards <invalid@invalid.invalid>
Newsgroups	comp.os.linux.development.apps
Subject	Re: termios
Date	2011-06-26 02:27 +0000
Organization	PANIX Public Access Internet and UNIX, NYC
Message-ID	<iu65dr$ijj$1@reader1.panix.com> (permalink)
References	(3 earlier) <itik9n$1bh$1@dont-email.me> <4dfce742$0$30775$ba4acef3@reader.news.orange.fr> <itiv7i$9mj$1@dont-email.me> <4e04c885$0$30751$ba4acef3@reader.news.orange.fr> <iu2lqg$4pq$1@dont-email.me>

Show all headers | View raw

On 2011-06-24, Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote:
> On 24.6.11 8:28 , michel simian wrote:
>> Tauno Voipio ??crivit de sa plume:
>>
>>> Attached is a module running RS-485 packet traffic under
>>> Linux on an Atmel AT91RM920 serial port with hardware control
>>> of transmit enable.
>>
>> So, it was a bit difficult to adapt, -I'm speaking about your sample
>> - but I realize that my kernel was a little bit too old (2.6.26).
>> Some of serial.h defintion was'nt there. I tried it on a 2.6.32, and
>> I had to find the include files containing some define of ioctl...
>> Then finally, I install a 2.6.35 and I could read the device's
>> answer. But I could not find how to disable the automatic echoing.
>> modifying the CREAD termios bit will block the write. modifying the
>> ECHO termios bit doesn't have any effect.
>>
>> I have to try and to search more. :)
>
> The echo is in hardware - learn about RS-485.

What he said. :)


> The transmit and receive use the same wires, so everything sent to
> the bus ends up t the own receiver, too.

Sometimes there's a jumper that controls the read-back of tx data.  If
not, you're going to have to write your software so that it ignores
the echoed data.

-- 
Grant

Back to comp.os.linux.development.apps | Previous | Next — Previous in thread | Find similar

Thread

termios michel simian <michel@simian.fr> - 2011-06-17 17:14 +0200
  Re: termios Jan Panteltje <pNaonStpealmtje@yahoo.com> - 2011-06-17 17:01 +0000
  Re: termios Grant Edwards <invalid@invalid.invalid> - 2011-06-17 20:19 +0000
    Re: termios michel simian <michel@simian.fr> - 2011-06-18 17:17 +0200
      Re: termios Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2011-06-18 19:38 +0300
        Re: termios michel simian <michel@simian.fr> - 2011-06-18 20:01 +0200
          Re: termios Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2011-06-18 22:44 +0300
            Re: termios michel simian <michel@simian.fr> - 2011-06-19 06:56 +0200
            Re: termios michel simian <michel@simian.fr> - 2011-06-24 19:28 +0200
              Re: termios Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2011-06-24 21:42 +0300
                Re: termios Grant Edwards <invalid@invalid.invalid> - 2011-06-26 02:27 +0000

csiph-web