Elektron Musical Instruments

Hello, yesterday my computer crashed. 

It doesn't happen often, maybe twice a year, but anyway it crashed with
a fatal exception. I booted back into windows, no problem with the
computer itself. 

This locked up the Sidstation. I could turn it off and back on, but I
could not go into patch selector mode, then it frooze up. The only way
to "unlock" it was to do a system reset, and loosing all the patches. By
sheer luck, I did a backup of all patches on sunday.

I noticed during the crash (while computer displayed bluescreen) that
the Sidstation MIDI activity went crazy. All four leds blinked
frantically.

So what happened - did it crash because it received bad MIDI signals?
Can a computer crash result in the computer spitting out dangerous MIDI
signals?
Does the Sidstation do Active sensing or something? Will a computer
crash trouble that?
What can I do to prevent this from happening again? 


(Maybe I was remotely punished by Elektron for wanting more
functionality, i guess they have a little world-wide radio transmitter
in the SID that is connected to the
Send-goobeligook-to-patch-memory-chip :-)


Gisle

On Wed, 16 Feb 2000, Gisle Martens Meyer wrote:

> I noticed during the crash (while computer displayed bluescreen) that
> the Sidstation MIDI activity went crazy. All four leds blinked
> frantically.

When this happens the diodes have nothing to do with what is printed next
to them. The frantic flickering just means that the processor has made a
"bezerk crash" and is currently destroying your patch memory! :) Notice
that all of the LED's were flickering - not just MIDI data.

> So what happened - did it crash because it received bad MIDI signals?
> Can a computer crash result in the computer spitting out dangerous MIDI
> signals?

Sounds very unlikely. If the SidStation receives illegal MIDI messages it
will reset. The only dangerous occasion is if it receives the exact 
patchdump header, and the messages continues for too long, overwriting the
memory. But getting the MIDI interface to output this message just by
coincidence is like one one on a billion.

> Does the Sidstation do Active sensing or something? Will a computer
> crash trouble that?

The SidStation ignores Active sensing! :)

> What can I do to prevent this from happening again? 

Mystery crashes are hard to avoid. Could be that the same thing that got
your PC to crash also crashed the SidStation (really high electromagnetic
interference, or power supply failure).

   __
__///Daniel Hansson           |   SidStation - MOS6581 Synthesis
\XX/ daniel@...   |         www.sidstation.com

>Sounds very unlikely. If the SidStation receives illegal MIDI messages it
>will reset.

would it be better if it just ignored illegal midi messages? i have a nord
micro and it never resets itself ...
(not knocking the sidstation, i've only had it reset once)..

>The SidStation ignores Active sensing! :)


what is active sensing? ... monitoring controller data?


>Mystery crashes are hard to avoid. Could be that the same thing that got
>your PC to crash also crashed the SidStation (really high electromagnetic
>interference, or power supply failure).


weird that a synth can 'crash' .. it's like a computer :)

androo

On Wed, 16 Feb 2000, andrew sargeant wrote:

> From: "andrew sargeant" <androo@...>
> 
> >Sounds very unlikely. If the SidStation receives illegal MIDI messages it
> >will reset.
> 
> would it be better if it just ignored illegal midi messages? i have a nord
> micro and it never resets itself ...

The thing is that illegal MIDI should never occur. The SidStation ignores
illegal messages when it can, but when illegal bytes are received in the
middle of a message it starts getting dangerous. The SidStation gets out
of sync, and I choose to reset the machine. But this never happens in
normal use, only if the MIDI chords are inserted/removed in the middle of
a message. And this is not dangerous - you only get the chance of a reset.

It's better to handle a critical situation than to ignore it. 

> (not knocking the sidstation, i've only had it reset once)..

After the update I hope it will never reset anymore.

> >The SidStation ignores Active sensing! :)
> 
> what is active sensing? ... monitoring controller data?

Some synths/sequencers send an Active sensing byte every now and then to
tell that it's there ($FE if I remember correctly). Modules attached can
take action (muting itself) if active sensing suddenly dissappears,
because that means that the MIDI connection probably is broken. But I
don't know of any instrument that actually uses it.

> >Mystery crashes are hard to avoid. Could be that the same thing that got
> >your PC to crash also crashed the SidStation (really high electromagnetic
> >interference, or power supply failure).
> 
> weird that a synth can 'crash' .. it's like a computer :)

It _is_ a computer! With an operating system, graphics subsystem etc just
lika a computer. Only so much more devoted to one single thing, and using
it's resources much better (try booting Windows on a 2MHz 8/16-bit
processor with 32k ROM 32k RAM! :). 

Computer controlled it is! :)

   __
__///Daniel Hansson           |   SidStation - MOS6581 Synthesis
\XX/ daniel@...   |         www.sidstation.com