PortMidi

v5.1.2

PortMidi v5.1.2 PortMidi View Source

The entry module of portmidi. Through this module you can open and close devices, listen on input devices, or write to output devices.

Link to this section Summary

Types

message()
timestamp()

Functions

close(device_type, device)

Terminates the GenServer held by the device argument, and closes the PortMidi stream. If the type is an input, and listen/2 was called on it, it also shuts down the listening process. Using the given device after calling this method will raise an error

devices()

Returns a map with input and output devices, in the form of PortMidi.Device structs

listen(input, pid)

Starts a listening process on the given input, and returns :ok. After calling this method, the process with the given pid will receive MIDI events in its mailbox as soon as they are emitted from the device

open(atom, device_name)

Opens a connection to the input device with name device_name

open(atom, device_name, latency \\ 0)

Opens a connection to the output device with name device_name

start(type, args)

Starts the :portmidi application. Under the hood, starts the Portmidi.Listeners GenServer, that holds all the listeners to input devices

write(output, message)

Writes a MIDI event to the given output device. message can be a tuple {status, note, velocity}, a tuple {{status, note, velocity}, timestamp} or a list [{{status, note, velocity}, timestamp}, ...]. Returns :ok on write

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message() View Source 
message() :: {byte(), byte(), byte()}

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timestamp() View Source 
timestamp() :: byte()

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close(device_type, device) View Source 
close(atom(), pid()) :: :ok

Terminates the GenServer held by the device argument, and closes the PortMidi stream. If the type is an input, and listen/2 was called on it, it also shuts down the listening process. Using the given device after calling this method will raise an error.

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devices() View Source 
devices() :: %{
  input: [
    %PortMidi.Device{
      input: term(),
      interf: term(),
      name: term(),
      opened: term(),
      output: term()
    },
    ...
  ],
  output: [
    %PortMidi.Device{
      input: term(),
      interf: term(),
      name: term(),
      opened: term(),
      output: term()
    },
    ...
  ]
}

Returns a map with input and output devices, in the form of PortMidi.Device structs

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listen(input, pid) View Source 
listen(pid(), pid()) :: :ok

Starts a listening process on the given input, and returns :ok. After calling this method, the process with the given pid will receive MIDI events in its mailbox as soon as they are emitted from the device.

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open(atom, device_name) View Source 
open(:input, <<_::0>>) :: {:ok, pid()} | {:error, atom()}

Opens a connection to the input device with name device_name.

Returns the pid to the corresponding GenServer. Use this pid to call listen/2.

If Portmidi can't open the device, a tuple {:error, reason} is returned. Check src/portmidi_shared.c#makePmErrorAtom for all possible errors.

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open(atom, device_name, latency \\ 0) View Source 
open(:output, <<_::0>>, non_neg_integer()) :: {:ok, pid()} | {:error, atom()}

Opens a connection to the output device with name device_name.

Returns the pid to the corresponding GenServer. Use this pid to call write/2.

If Portmidi can't open the device, a tuple {:error, reason} is returned. Check src/portmidi_shared.c#makePmErrorAtom for all possible errors.

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start(type, args) View Source

Starts the :portmidi application. Under the hood, starts the Portmidi.Listeners GenServer, that holds all the listeners to input devices.

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write(output, message) View Source 
write(pid(), message()) :: :ok
write(pid(), {message(), timestamp()}) :: :ok
write(pid(), [{message(), timestamp()}, ...]) :: :ok

Writes a MIDI event to the given output device. message can be a tuple {status, note, velocity}, a tuple {{status, note, velocity}, timestamp} or a list [{{status, note, velocity}, timestamp}, ...]. Returns :ok on write.