From a209b48720c9bc086bdf87265257a1b6c3158e87 Mon Sep 17 00:00:00 2001
From: Ashley Strahle <ash@jackofclubs.com.au>
Date: Thu, 25 Jun 2026 22:51:44 +0000
Subject: [PATCH] Add second USB MIDI interface (LPX MIDI) for Programmer mode

- Interface 1 (DAW): Button presses -> Loopy Pro
- Interface 2 (MIDI): SysEx + LED control <- Loopy Pro
- Both interfaces polled in update()
- Sends on DAW interface (like real Launchpad X)
---
 src/midi_transport.cpp | 67 ++++++++++++++++++++++++++++++------------
 1 file changed, 49 insertions(+), 18 deletions(-)

diff --git a/src/midi_transport.cpp b/src/midi_transport.cpp
index e498760..68b8df2 100644
--- a/src/midi_transport.cpp
+++ b/src/midi_transport.cpp
@@ -2,7 +2,8 @@
 #include <Arduino.h>
 #include "Adafruit_TinyUSB.h"
 
-static Adafruit_USBD_MIDI usb_midi;
+static Adafruit_USBD_MIDI usb_midi_daw;   // Interface 1: DAW/Session
+static Adafruit_USBD_MIDI usb_midi_midi;  // Interface 2: MIDI/Programmer
 
 UsbMidiTransport::UsbMidiTransport() : initialized(false) {
 }
@@ -11,27 +12,32 @@ UsbMidiTransport::~UsbMidiTransport() {
 }
 
 bool UsbMidiTransport::begin() {
-    Serial.println("[MIDI] Setting up USB MIDI device...");
+    Serial.println("[MIDI] Setting up USB MIDI device (dual interface)...");
 
-    TinyUSBDevice.setManufacturerDescriptor("Ashley Strahle");
-    TinyUSBDevice.setProductDescriptor("Loopy Foot Controller");
-    TinyUSBDevice.setSerialDescriptor("LFMIDI001");
+    TinyUSBDevice.setManufacturerDescriptor("Novation");
+    TinyUSBDevice.setProductDescriptor("Launchpad X");
+    TinyUSBDevice.setSerialDescriptor("LPX00001");
     TinyUSBDevice.begin(0);
 
-    if (!usb_midi.begin()) {
-        Serial.println("[MIDI] ERROR: USB MIDI init failed");
+    // Initialize both MIDI interfaces
+    if (!usb_midi_daw.begin()) {
+        Serial.println("[MIDI] ERROR: DAW MIDI init failed");
+        return false;
+    }
+    if (!usb_midi_midi.begin()) {
+        Serial.println("[MIDI] ERROR: MIDI MIDI init failed");
         return false;
     }
 
     if (TinyUSBDevice.mounted()) {
-        Serial.println("[MIDI] Re-enumerating with MIDI interface...");
+        Serial.println("[MIDI] Re-enumerating with dual MIDI interface...");
         TinyUSBDevice.detach();
         delay(10);
         TinyUSBDevice.attach();
     }
 
     initialized = true;
-    Serial.println("[MIDI] USB MIDI ready - enumerating...");
+    Serial.println("[MIDI] USB MIDI ready - dual interface enumerating...");
     return true;
 }
 
@@ -46,9 +52,10 @@ void UsbMidiTransport::update() {
                       TinyUSBDevice.mounted() ? "YES" : "NO");
     }
 
-    while (usb_midi.available()) {
+    // Poll DAW interface (interface 1)
+    while (usb_midi_daw.available()) {
         uint8_t packet[4];
-        if (usb_midi.readPacket(packet)) {
+        if (usb_midi_daw.readPacket(packet)) {
             MidiEvent event;
             parse_midi_packet(packet, 4, event);
 
@@ -61,7 +68,31 @@ void UsbMidiTransport::update() {
                 case MidiEvent::PITCH_BEND: type_str = "PB"; break;
                 default: break;
             }
-            Serial.printf("[MIDI IN] Ch:%d %s:%d:%d\n", event.channel, type_str, event.data1, event.data2);
+            Serial.printf("[MIDI IN DAW] Ch:%d %s:%d:%d\n", event.channel, type_str, event.data1, event.data2);
+
+            if (receive_callback) {
+                receive_callback(event);
+            }
+        }
+    }
+
+    // Poll MIDI interface (interface 2) - for Programmer mode LED control
+    while (usb_midi_midi.available()) {
+        uint8_t packet[4];
+        if (usb_midi_midi.readPacket(packet)) {
+            MidiEvent event;
+            parse_midi_packet(packet, 4, event);
+
+            const char* type_str = "UNK";
+            switch (event.type) {
+                case MidiEvent::NOTE_ON: type_str = "NOTE_ON"; break;
+                case MidiEvent::NOTE_OFF: type_str = "NOTE_OFF"; break;
+                case MidiEvent::CONTROL_CHANGE: type_str = "CC"; break;
+                case MidiEvent::PROGRAM_CHANGE: type_str = "PC"; break;
+                case MidiEvent::PITCH_BEND: type_str = "PB"; break;
+                default: break;
+            }
+            Serial.printf("[MIDI IN MIDI] Ch:%d %s:%d:%d\n", event.channel, type_str, event.data1, event.data2);
 
             if (receive_callback) {
                 receive_callback(event);
@@ -77,22 +108,22 @@ void UsbMidiTransport::on_midi_receive(std::function<void(const MidiEvent&)> cal
 void UsbMidiTransport::send_note_on(uint8_t channel, uint8_t note, uint8_t velocity) {
     if (!initialized) return;
     uint8_t packet[4] = {0x09, (uint8_t)(0x90 | (channel - 1)), note, velocity};
-    usb_midi.writePacket(packet);
-    Serial.printf("[MIDI OUT] Ch:%d NOTE_ON:%d:%d\n", channel, note, velocity);
+    usb_midi_daw.writePacket(packet);
+    Serial.printf("[MIDI OUT DAW] Ch:%d NOTE_ON:%d:%d\n", channel, note, velocity);
 }
 
 void UsbMidiTransport::send_note_off(uint8_t channel, uint8_t note, uint8_t velocity) {
     if (!initialized) return;
     uint8_t packet[4] = {0x08, (uint8_t)(0x80 | (channel - 1)), note, velocity};
-    usb_midi.writePacket(packet);
-    Serial.printf("[MIDI OUT] Ch:%d NOTE_OFF:%d:%d\n", channel, note, velocity);
+    usb_midi_daw.writePacket(packet);
+    Serial.printf("[MIDI OUT DAW] Ch:%d NOTE_OFF:%d:%d\n", channel, note, velocity);
 }
 
 void UsbMidiTransport::send_cc(uint8_t channel, uint8_t cc, uint8_t value) {
     if (!initialized) return;
     uint8_t packet[4] = {0x0B, (uint8_t)(0xB0 | (channel - 1)), cc, value};
-    usb_midi.writePacket(packet);
-    Serial.printf("[MIDI OUT] Ch:%d CC:%d:%d\n", channel, cc, value);
+    usb_midi_daw.writePacket(packet);
+    Serial.printf("[MIDI OUT DAW] Ch:%d CC:%d:%d\n", channel, cc, value);
 }
 
 bool UsbMidiTransport::is_connected() {