Initial commit: Arduino Uno Q USB Audio Synth project

- USB gadget (UAC1 + MIDI) with boot persistence - USB host mode with auto-detection - Pure Data synth patch with ALSA + UDP netreceive MIDI input - MIDI rawmidi-to-UDP bridge (midi-bridge.py) - LED matrix visualization (led-matrix-viz.py via arduino-router RPC) - MCU sketch for LED matrix control (Arduino_RouterBridge + ArduinoGraphics) - Conftest/OPA Rego policy validation suite for .pd files - gen_synth_pd.py: programmatic .pd file generator - System services: midi-bridge, led-matrix-viz, pd-synth-auto, usb-role-detect - Justfile with deploy, enable, diagnostic recipes - Diagnostic script (diag.sh)
2026-06-22 22:46:36 -07:00
commit 8cd796e3dd
38 changed files with 2681 additions and 0 deletions
@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+"""Bridge raw MIDI device to Pd via UDP. For host mode with MPK Mini.
+
+Sends parsed MIDI messages as Pd-style 'midi status data1 data2;' strings
+to UDP ports for Pd (8081) and LED matrix visualization (8082).
+"""
+import os, socket, time, select, struct
+
+MIDI_DEV = os.environ.get("MIDI_BRIDGE_DEV", "/dev/snd/midiC0D0")
+PD_HOST = os.environ.get("MIDI_BRIDGE_HOST", "127.0.0.1")
+PD_PORT = int(os.environ.get("MIDI_BRIDGE_PORT", "8081"))
+VIZ_PORT = int(os.environ.get("VIZ_PORT", "8082"))
+
+def midi_msg(status, data1, data2=None):
+    if data2 is not None:
+        return f"midi {status} {data1} {data2};"
+    return f"midi {status} {data1};"
+
+def main():
+    while not os.path.exists(MIDI_DEV):
+        time.sleep(0.5)
+
+    fd = os.open(MIDI_DEV, os.O_RDWR | os.O_NONBLOCK)
+    os.set_blocking(fd, False)
+    poll = select.poll()
+    poll.register(fd, select.POLLIN)
+
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+
+    running = True
+    buf = bytearray()
+    while running:
+        try:
+            events = poll.poll(500)
+            for f, flags in events:
+                if flags & select.POLLIN:
+                    data = os.read(fd, 1024)
+                    if not data:
+                        continue
+                    for byte in data:
+                        if byte & 0x80:
+                            if len(buf) > 0 and buf[0] >= 0x80:
+                                _flush(sock, buf, PD_HOST, PD_PORT, VIZ_PORT)
+                            buf = bytearray([byte])
+                        else:
+                            buf.append(byte)
+                            if len(buf) >= 3 and (buf[0] & 0xE0) in (0x80, 0x90, 0xA0, 0xB0, 0xE0):
+                                _flush(sock, buf, PD_HOST, PD_PORT, VIZ_PORT)
+                                buf = bytearray()
+                            elif len(buf) >= 2 and (buf[0] & 0xE0) in (0xC0, 0xD0):
+                                _flush(sock, buf, PD_HOST, PD_PORT, VIZ_PORT)
+                                buf = bytearray()
+        except (BlockingIOError, OSError) as e:
+            if isinstance(e, OSError) and e.errno == 19:
+                time.sleep(1)
+                continue
+            if not isinstance(e, BlockingIOError):
+                raise
+        except KeyboardInterrupt:
+            running = False
+
+    os.close(fd)
+    sock.close()
+
+def _flush(sock, buf, pd_host, pd_port, viz_port):
+    status = buf[0]
+    if (buf[0] & 0xF0) == 0xF0:
+        return
+    data1 = buf[1]
+    data2 = buf[2] if len(buf) >= 3 else None
+    msg = midi_msg(status, data1, data2)
+    sock.sendto(msg.encode(), (pd_host, pd_port))
+    sock.sendto(msg.encode(), (pd_host, viz_port))
+
+if __name__ == "__main__":
+    main()