Analogue-sequencer

> Can the P3  sed syx/ex via the aux?  I want to control some 
> parameters like 
> decay for the FM old yamaha synths.

Sysex is not implemented, and probably wont be unless there are some
very simple common commands people need. The problem is each aux only
holds one data byte, so I would need somewhere to store the rest of the
sysex string. Checksum generation would be difficult too.
One possibility would be to hard-code some sysex strings into specific
events - but there could be so many different ones it would be hard to
choose which ones to provide.
I'm not keen on using sysex in real-time. Midi timing is bad enough with
multiple 2 or 3 byte messages. Getting into 5 and 6 byte sysex strings
can only make it sloppy.
 
> What controls exactly the lenght parameter? I want to 
> understand that it is 
> the decay control, but I am not sure since it is different on 
> each synth.

The length controls the proportion of each step that the 'gate' is on
for (i.e. time between note-on and note-off).
The value is in twelfths - so a length of 6 means the gate is on for 50%
of the length of the step.

> What is the default lenght number  0 or 4?

Now you're confusing me - minimum length is 1. Unless you mean something
else...

> Is any way to turn a row to the default other than turning by 
> hand them to 
> the left?

You can use the Sculpt option to set all the steps to the same value in
one pass.

Cheers,
Colin f