On Sun, 2006-11-12 at 17:28 +0100, Pieter Palmers wrote:
[regarding midi over firewire]
Note that this is already implemented in FreeBob.
There is nothing
preventing us from setting up a (random number here)-channel MIDI link
over Firewire between one or more devices.
A major issue however is discovering the devices and negotiating a
common stream format. This is not specified by the MMA, this spec only
describes the actual transfer of the MIDI bytes.
Pieter, I am not sure that I follow you correctly here. Using bad
car-anology: Is this like as if you have already build "The Golden Gate
Bridge", but there are still no "Highways" connecting to it? That there
is a sinc to throw the bytes into but no way for alsa to know about it?
In other words; is a device like M-Audio's 4ch audio in/out + 3 octave
keyboard useful as a performance instrument under Linux, or will the
keyboard be dead?
Another showstopper is that every sender will need his
own firewire
isochronous channel to send its data on, so that limits the number of
devices to 16. Keep in mind that the Firewire bus is one single domain
(for the Isochronous traffic), i.e. everybody sees everything.
Uhmm yes, but as I read from the paper, the midi transfer rate is (or
can be) quadrupled. Given that a home/stage setup with a single player
on a single cable works just fine latency-wise, wouldn't then 16*4 be
quite enough? At the risk of paraphrazing Bill Gates, but 64 staves
ought to be enough for anyone ... You could fit in two symphonic
orchestras, mixed choir, a couple of organs, a big band as well as an
extended Irish folk-group into that budget (and then some.)
Jokes aside: I don't see any external firewire computing devices where
one could send all those midi2 messages to. Anyone else?
When using asynchronous traffic these restrictions
don't apply but then
you lose the 'broadcast' advantage, making everything more complex.
Pieter
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