[PD] Human interface Devices for PD
Martin Peach
martin.peach at sympatico.ca
Mon Jul 31 02:57:33 CEST 2006
thewade wrote:
>
>
> Maybe you can answer a couple of general questions for me?
>
> Is MIDI capable of doing continuous stuff?
>
MIDI sends triples or pairs of bytes over a serial interface so
continuous values are quantized at the MIDI data rate.
> What is it's maximum sampling/transmission rate for MIDI?
>
At 1/31250 second per bit, there are ten bits per serial byte, so a pair
of controller number and value will take 20/31250 seconds to be
transmitted. That's 64 microseconds per message best case, or 1562.5
updates per second. For full resolution you need 4 bytes, so it runs
half as fast, and if more than one controller is active, slower still.
>
> Thanks for the schematic! I think what intimidated me most is the
> interfacing of the software to the hardware: my C/C++ code is a bit
> rusty...
> That schematic is pretty cool though! So many possabilities!
The program I have for it just sends MIDI continuous controller messages
as fast as it can send them whenever an input changes. In PD it uses
[ctlin]. One version I built has a two-axis accelerometer. The MIDI data
is used to move an object in a GEM window.
Martin
More information about the Pd-list
mailing list