Phase 6: SID audio (5 cues + fault stinger)

src/main.c

@@ -2,17 +2,19 @@
 //
 // Flow:
 //   1. memmap_setup()      — bank out KERNAL/BASIC/CHAR ROM.
-//   2. score_init()        — zero both player scores.
-//   3. game_init()         — enter the TITLE state (which also loads
-//                            the title screen and renders the score
-//                            bar).
-//   4. rasterirq_setup()   — install the single RIRQ at line 311.
+//   2. audio_init()        — set SID master volume, no filter, silence
+//                            all 3 voices.  Phase 6 addition.
+//   3. score_init()        — zero both player scores.
+//   4. game_init()         — enter the TITLE state (which also loads
+//                            the title screen, renders the score bar,
+//                            and calls audio_state_enter(STATE_TITLE)).
+//   5. rasterirq_setup()   — install the single RIRQ at line 311.
 //                            The IRQ handler increments frame_count
 //                            and calls game_step() once per frame.
-//   5. while (1) {}         — idle.  All per-frame work happens in
+//   6. while (1) {}         — idle.  All per-frame work happens in
 //                            the IRQ handler.
 //
-// In Phase 4 step 5 was `while (1) game_step();` — a busy-wait that
+// In Phase 4 step 6 was `while (1) game_step();` — a busy-wait that
 // called game_step as fast as the CPU could, so the "frame counter"
 // was CPU-bound.  In Phase 5 the busy-wait is gone: game_step is
 // called from the raster IRQ at exactly 50 Hz, so state durations
@@ -20,6 +22,7 @@
 // what the CPU is doing between IRQs.
 
 #include "memmap.h"
+#include "audio.h"
 #include "game.h"
 #include "score.h"
 #include "tick.h"
@@ -31,6 +34,7 @@
 int main(void)
 {
 	memmap_setup();
+	audio_init();
 	score_init();
 	game_init();
 	rasterirq_setup();