midirx-handler.md

midirx (short: mrx)

The MIDI receive handler is part of the System element and is triggered when MIDI messages are received. It provides access to incoming MIDI data via the global midi object.

The midi Object

When the handler is triggered, the midi global object contains the received MIDI message:

Property	Description
midi.ch	MIDI channel
midi.cmd	MIDI command (status byte)
midi.p1	MIDI parameter 1 (note/CC number)
midi.p2	MIDI parameter 2 (velocity/value)

MIDI RX Control Functions (global)

Short	Human Name	Description
mre	midirx_enabled	Enable/disable MIDI RX processing (1=enabled, 0=disabled)
mrs	midirx_sync	Enable/disable MIDI sync messages (clock, start, stop)

Custom Callback Pattern

You can define a custom midirx_cb callback on elements to handle MIDI messages:

function self.midirx_cb(self, event, header)
    -- event[1] = channel, event[2] = command, event[3] = param1, event[4] = param2
    -- header[1] = source info
end

Default Action String

local ch,cmd,param1,param2=midi.ch,midi.cmd,midi.p1,midi.p2

This extracts the MIDI message components into local variables for use in custom code.

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