The Be Book - System Overview - The Midi Kit
A BMidiPort
object reads and writes MIDI data through a MIDI hardware
port. A MIDI hardware port has an input side (MIDI-In) and an output side
(MIDI-Out); you can use a single
BMidiPort
object to communicate with both sides. Also, you can create and use any number of
BMidiPort
objects in your application—multiple
BMidiPort
objects can open and use the same hardware port at the same time.
You identify a MIDI port by name, passing it to the
BMidiPort
constructor or
Open()
function. Use the
GetDeviceName()
function to retrieve the names of the MIDI ports. The ports are closed through
Close();
they're automatically closed when the
BMidiPort
object is destroyed.
On a Macintosh, there are two midi ports:
"midi1" is the modem port.
"midi2" is the printer port.
On Intel hardware…
A
BMidiPort
object can only open one port at a time.
Running a
BMidiPort
corresponds to MIDI-In: When you tell a
BMidiPort
to run (through the
Start()
function) the object begins reading from
MIDI-In and spraying the MIDI messages to its connected objects.
On the other side, the MIDI hook functions
(NoteOn(),
NoteOff(),
etc.) send MIDI messages to MIDI-Out.
It's possible to use the same
BMidiPort
object to accept data from
MIDI-In and broadcast different data to MIDI-Out. You can even connect a
BMidiPort
object to itself to create a "MIDI through" effect: Anything
that shows up at the MIDI-In port will automatically be sent out the
MIDI-Out port.
