[sdiy] Communications with voices in a polyphonic synth

[Neil Johnson]

Hi,

cheater cheater wrote:
> One thing that makes RS a good standard is the fact that .. it's a
> standard.

A rather small electrical standard at that.

> Your cut down CAN is not going to be standard; in 10 years
> it might be difficult for you to recreate the protocol.

CAN is both an electrical and protocol standard, considerably more  
than RS485, so difficult to compare meaningfully.

> RS is well documented.

True, but then so is CAN - just a lot more pages.

> For 8 voices that's 10 + 80 + 16 packets. That's 106 packets. In 9-bit
> mode that's 954 bits,

I think you mean 1166 bits.

> so round it up to 1 kilobit, which has to happen
> in 0.25 ms. This means 4 Kbit per 1ms so 4 Mbit per 1 sec so 4 Mb/s.
> For 64 voices it's 8 times more, so 32 Mb/s.

You don't need to send voice patch "matrix" data with every key-on  
event, unless you want to support dynamic multitimbrality.

> What's more important is that if you want to one day support OSC,

... YYyyyes, once Tom has fitted a Gigabit Ethernet socket to cope  
with the highly verbose protocol ... sure ...

Neil
--
http://www.njohnson.co.uk