[PD] Comport can't read serial devices when soundcard is plugged in

[Martin Peach]

It's very likely the sound card is using a lot more bandwidth of the USB 
hub than the arduino. If it's not a laptop you can usually plug into a 
different hub on the same machine.
The random dropouts of the serial connection sound like a problem with 
the cable or connectors, or else something is plugged into the arduino 
that's taking too much current from the USB.

Martin

On 2011-07-09 11:26, Pierre Massat wrote:
> The problem isn't really solved at all.
>
> The USB soundcard doesn't seem to completely prevent [comport] to detect
> my uno board (I've been playing with both plugged in for the past 2
> hours). But [comport] seems to be a little temperamental. I have to open
> and close Pd several times, and change the USB port i'm using, for it to
> detect the arduino board (though changing the port may not have any
> impact). Opening and closing the port i'm using in [comport] doesn't
> seem to have any effect either.
>
> The thing is, as i said in a previous post, that there's something weird
> about my serial ports on my ubuntu machine. The Arduino IDE detects my
> boards about every other time, or just looses it for no apparent reason.
> So maybe it's a problem with Ubuntu? [comport] seems to have a much more
> predictable behaviour in windows (which i can't use because i need low
> latency).
>
> Any Gandalf out there to help me out?
>
> pierre
>
>
> 2011/7/9 Martin Peach <martin.peach at sympatico.ca
> <mailto:martin.peach at sympatico.ca>>
>
>     On 2011-07-09 08:48, Pierre Massat wrote:
>
>         UPDATE : comport is now working as expected, and my arduino uno
>         board is
>         now friends with my USB soundcard.
>
>
>     So what was the problem?
>
>
>
>         I guess it's high time i started reading the first volume of
>         Harry Potter.
>
>
>     Maybe read some Crowley about banishing daemons before plugging in...
>
>     Martin
>
>
>         Pierre
>
>         2011/7/9 Ingo <ingo at miamiwave.com <mailto:ingo at miamiwave.com>
>         <mailto:ingo at miamiwave.com <mailto:ingo at miamiwave.com>>>
>
>
>             Similar problem here. I had an Arduino (USB) and a LCD
>         display (RS232)
>             working together very well with two [comport] objects on my old
>             mainboard.
>             With the new board either one by themselves is working fine
>         but both
>             of them
>             connected bidirectional doesn't work. As soon as I connect
>         the serial in
>             from the display (which is supposed to get the keypad of the
>         serial
>             display)
>             I get a lots of crazy data coming in. After a while either
>         [comport]
>             or Pd
>             altogether crashes.
>
>             The LCD [comport] should only receive digital buttons
>         on/off. While the
>             arduino sends buttons plus four analogue INs from a joystick
>         and two
>             foot
>             pedals.
>             All cables are very short, so the problematic behaviour can't be
>             caused by
>             the cable length. Without connecting the serial out of the
>         display
>             to the
>             serial in of the computer everything works fine.
>
>             I was also suspecting an error in comport where the data of two
>             instances of
>             two [comport] objects get mixed up. It looks like the
>         analogue data
>             from the
>             arduino board gets forwarded to the second RS232 [comport]
>         of the LCD.
>
>             Ingo
>
>
>             __________________________________________
>             Von: pd-list-bounces at iem.at <mailto:pd-list-bounces at iem.at>
>         <mailto:pd-list-bounces at iem.at <mailto:pd-list-bounces at iem.at>__>
>             [mailto:pd-list-bounces at iem.at
>         <mailto:pd-list-bounces at iem.at> <mailto:pd-list-bounces at iem.at
>         <mailto:pd-list-bounces at iem.at>__>] Im
>
>             Auftrag von
>             Pierre Massat
>             Gesendet: Samstag, 9. Juli 2011 13:38
>             An: pd-list
>             Betreff: [PD] Comport can't read serial devices when
>         soundcard is
>             plugged in
>
>             Hi all!
>
>             After having had to deal with a "bug" in pduino (see Arduin
>         is drivin me
>             mad), i wrote a small sketch for the board and a patch using
>             comport. It was
>             working fine until i decided to actually try it with my
>         audio patch.
>             It turns out that my external USB soundcard prevents comport
>         from
>             working
>             properly. It can't open the arduino board, and can't event
>         detect serial
>             devices ("devices" yields an empty message in the console).
>         As soon as i
>             unplug the soundcard, everything works fine again.
>
>             I think i'm beginning to realize that a lot of things have to be
>             taken care
>             off, and i know that my patch and sketch are way to simple
>         to take
>             this kind
>             of issue into account (i wish i could switch back to Pduino and
>             firmata).
>
>             So my question is : is this behaviour normal, or is it bug
>         in comport?
>
>             Thanks!
>
>             Pierre
>
>
>
>
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