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 +1,100 @@
+#!/usr/bin/env python3
+"""Listen for MIDI events via UDP and display note activity on LED matrix.
+
+Uses RPC requests (not notifications) for reliability, with rate limiting.
+"""
+import socket, msgpack, time, os, re
+
+VIZ_PORT = int(os.environ.get("VIZ_PORT", "8082"))
+ROUTER_SOCK = os.environ.get("ROUTER_SOCK", "/var/run/arduino-router.sock")
+DECAY_FRAMES = int(os.environ.get("DECAY_FRAMES", "8"))
+MIN_INTERVAL = 1 / 15
+
+COLS = 13
+ROWS = 8
+
+def pack_frame(pixels):
+    bits = 0
+    for row in range(ROWS):
+        for col in range(COLS):
+            if pixels[row][col]:
+                bits |= 1 << (row * COLS + col)
+    return (bits & 0xFFFFFFFF, (bits >> 32) & 0xFFFFFFFF,
+            (bits >> 64) & 0xFFFFFFFF, (bits >> 96) & 0xFFFFFFFF)
+
+def main():
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+    sock.bind(("0.0.0.0", VIZ_PORT))
+    sock.setblocking(False)
+
+    router = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    router.settimeout(2)
+    router.connect(ROUTER_SOCK)
+    packer = msgpack.Packer()
+
+    active_notes = {}
+    last_frame = None
+    last_send = 0
+    buf = b""
+    msg_id = 0
+
+    while True:
+        now = time.monotonic()
+
+        try:
+            while True:
+                data, _ = sock.recvfrom(1024)
+                buf += data
+        except BlockingIOError:
+            pass
+
+        while b";" in buf:
+            msg, buf = buf.split(b";", 1)
+            msg = msg.decode().strip()
+            parts = msg.split()
+            if len(parts) >= 3 and parts[0] == "midi":
+                status = int(parts[1])
+                note = int(parts[2])
+                vel = int(parts[3]) if len(parts) >= 4 else 0
+                msg_type = status & 0xF0
+                if msg_type == 0x90 and vel > 0:
+                    active_notes[note] = DECAY_FRAMES
+                elif msg_type == 0x80 or (msg_type == 0x90 and vel == 0):
+                    active_notes.pop(note, None)
+
+        if now - last_send >= MIN_INTERVAL:
+            pixels = [[0] * COLS for _ in range(ROWS)]
+            for note, decay in list(active_notes.items()):
+                if decay <= 0:
+                    del active_notes[note]
+                    continue
+                active_notes[note] = decay - 1
+                note_min, note_max = 36, 96
+                row = 7 - int((note - note_min) / (note_max - note_min) * 7)
+                row = max(0, min(7, row))
+                col = note % 12
+                pixels[row][col] = 1
+
+            frame = pack_frame(pixels)
+            if frame != last_frame:
+                msg_id = (msg_id + 1) % 65535
+                params = [str(v) for v in frame]
+                req = packer.pack([0, msg_id, "draw_frame", params])
+                try:
+                    router.sendall(req)
+                    router.settimeout(0.3)
+                    router.recv(128)
+                    router.settimeout(2)
+                except socket.timeout:
+                    pass
+                except OSError:
+                    router.close()
+                    router = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+                    router.settimeout(2)
+                    router.connect(ROUTER_SOCK)
+                last_frame = frame
+            last_send = now
+
+if __name__ == "__main__":
+    main()