SPC700 to get notified when ports are written

src/app/emu/snes.cc

@@ -379,6 +379,41 @@ void SNES::VBlankRoutine() {
   // ...
 }
 
+void SNES::BootAPUWithIPL() {
+  // 1. Waiting for the SPC700 to be ready
+  while (!apu.IsReadySignalReceived()) {
+    // Active waiting (this can be optimized)
+  }
+
+  // 2. Setting the starting address
+  const uint16_t startAddress = 0x0200;
+  memory_.WriteByte(0x2142, startAddress & 0xFF);  // Lower byte
+  memory_.WriteByte(0x2143, startAddress >> 8);    // Upper byte
+  memory_.WriteByte(0x2141, 0xCC);                 // Any non-zero value
+  memory_.WriteByte(0x2140, 0xCC);                 // Signal to start
+
+  const int DATA_SIZE = 0x1000;  // 4 KiB
+
+  // 3. Sending data (simplified)
+  // Assuming a buffer `audioData` containing the audio program/data
+  uint8_t audioData[DATA_SIZE];  // Define DATA_SIZE and populate audioData as
+                                 // needed
+  for (int i = 0; i < DATA_SIZE; ++i) {
+    memory_.WriteByte(0x2141, audioData[i]);
+    memory_.WriteByte(0x2140, i & 0xFF);
+    while (memory_.ReadByte(0x2140) != (i & 0xFF))
+      ;  // Wait for acknowledgment
+  }
+
+  // 4. Running the SPC700 program
+  memory_.WriteByte(0x2142, startAddress & 0xFF);  // Lower byte
+  memory_.WriteByte(0x2143, startAddress >> 8);    // Upper byte
+  memory_.WriteByte(0x2141, 0x00);                 // Zero to start the program
+  memory_.WriteByte(0x2140, 0xCE);                 // Increment by 2
+  while (memory_.ReadByte(0x2140) != 0xCE)
+    ;  // Wait for acknowledgment
+}
+
 void SNES::HandleInput() {
   // ...
 }