Make MIDI card address flexible, add interrupts

src/glue.h

@@ -79,6 +79,9 @@ extern bool has_via2;
 extern uint32_t host_sample_rate;
 extern bool enable_midline;
 
+extern bool has_midi_card;
+extern uint16_t midi_card_addr;
+
 extern void machine_dump(const char* reason);
 extern void machine_reset();
 extern void machine_nmi();

src/main.c

@@ -131,6 +131,9 @@ bool enable_midline = false;
 bool ym2151_irq_support = false;
 char *cartridge_path = NULL;
 
+bool has_midi_card = false;
+uint16_t midi_card_addr;
+
 bool using_hostfs = true;
 
 uint8_t MHZ = 8;
@@ -528,6 +531,12 @@ usage()
 	printf("\tSuppress warning emitted when encountering a Rockwell extension on the 65C02\n");
 	printf("-longpwron\n");
 	printf("\tSimulate a long press of the power button at system power-on.\n");
+	printf("-midicard [<address>]\n");
+	printf("\tInstall a serial MIDI card at the specified address, or at $9F60 by default.\n");
+	printf("\tThe -sf2 option must be specified along with this option.\n");
+	printf("-sf2 <SoundFont filename>\n");
+	printf("\tInitialize MIDI synth with the specified SoundFont.\n");
+	printf("\tThe -midicard option must be specified along with this option.\n");
 #ifdef TRACE
 	printf("-trace [<address>]\n");
 	printf("\tPrint instruction trace. Optionally, a trigger address\n");
@@ -633,6 +642,18 @@ main(int argc, char **argv)
 			prg_path = argv[0];
 			argc--;
 			argv++;
+		} else if (!strcmp(argv[0], "-midicard")) {
+			argc--;
+			argv++;
+			has_midi_card = true;
+			if (argc && argv[0][0] != '-') {
+				midi_card_addr = 0x9f00 | ((uint16_t)strtol(argv[0], NULL, 16) & 0xff);
+				midi_card_addr &= 0xfff0;
+				argc--;
+				argv++;
+			} else {
+				midi_card_addr = 0x9f60;
+			}
 		} else if (!strcmp(argv[0], "-sf2")) {
 			argc--;
 			argv++;
@@ -1100,9 +1121,16 @@ main(int argc, char **argv)
 #endif
 	}
 
-	if (sf2_path) {
-		midi_init();
-		midi_load_sf2((uint8_t *)sf2_path);
+	if (sf2_path && has_midi_card) {
+		if (midi_card_addr < 0x9f60) {
+			fprintf(stderr, "Warning: Serial MIDI card address must be in the range of 9F60-9FF0\n");
+		} else {
+			midi_init();
+			midi_load_sf2((uint8_t *)sf2_path);
+		}
+	} else if (sf2_path || has_midi_card) {
+		fprintf(stderr, "Warning: -sf2 and -midicard must be specified together in order to enable the MIDI synth.\n");
+		has_midi_card = false;
 	}
 
 	if (cartridge_path) {
@@ -1634,7 +1662,7 @@ emulator_loop(void *param)
 			audio_render();
 		}
 
-		if (video_get_irq_out() || via1_irq() || (has_via2 && via2_irq()) || (ym2151_irq_support && YM_irq())) {
+		if (video_get_irq_out() || via1_irq() || (has_via2 && via2_irq()) || (ym2151_irq_support && YM_irq()) || (has_midi_card && midi_serial_irq())) {
 //			printf("IRQ!\n");
 			irq6502();
 		}

src/memory.c

@@ -198,12 +198,12 @@ real_read6502(uint16_t address, bool debugOn, int16_t bank)
 				return YM_read_status();
 			}
 			return 0x9f; // open bus read
-		} else if (address >= 0x9fc0 && address < 0x9fd0) {
-			// midi card
-			return midi_serial_read(address & 0xf, debugOn);
 		} else if (address >= 0x9fb0 && address < 0x9fc0) {
 			// emulator state
 			return emu_read(address & 0xf, debugOn);
+		} else if (has_midi_card && (address & 0xfff0) == midi_card_addr) {
+			// midi card
+			return midi_serial_read(address & 0xf, debugOn);
 		} else {
 			// future expansion
 			return 0x9f; // open bus read
@@ -278,11 +278,11 @@ write6502(uint16_t address, uint8_t value)
 				audio_render();
 				YM_write_reg(addr_ym, value);
 			}
-		} else if (address >= 0x9fc0 && address < 0x9fd0) {
-			midi_serial_write(address & 0xf, value);
 		} else if (address >= 0x9fb0 && address < 0x9fc0) {
 			// emulator state
 			emu_write(address & 0xf, value);
+		} else if (has_midi_card && (address & 0xfff0) == midi_card_addr) {
+			midi_serial_write(address & 0xf, value);
 		} else {
 			// future expansion
 		}

src/midi.c

@@ -131,6 +131,7 @@ static bool serial_midi_mutexes_initialized = false;
 #ifndef __EMSCRIPTEN__
 
 int handle_midi_event(void* data, fluid_midi_event_t* event);
+void midi_serial_iir_check(uint8_t sel);
 
 static uint8_t sysex_buffer[1024];
 static int sysex_bufptr;
@@ -143,7 +144,6 @@ static bool midi_initialized = false;
 
 static fluid_settings_t* fl_settings;
 static fluid_midi_driver_t* fl_mdriver;
-//static fluid_audio_driver_t* fl_adriver;
 static fluid_synth_t* fl_synth;
 static int fl_sf2id;
 
@@ -270,15 +270,15 @@ void midi_init()
     fl_mdriver = dl_new_fluid_midi_driver(fl_settings, handle_midi_event, &mregs[0]);
 
     midi_initialized = true;
-    printf("Initialized MIDI synth.\n");
+    fprintf(stderr, "Initialized MIDI synth at $%04X.\n", midi_card_addr);
 }
 
 void midi_load_sf2(uint8_t* filename)
 {
     if (!midi_initialized) return;
     fl_sf2id = dl_fs_sfload(fl_synth, (const char *)filename, true);
     if (fl_sf2id == FLUID_FAILED) {
-        printf("Unable to load soundfont.\n");
+        fprintf(stderr, "Unable to load soundfont.\n");
     }
 }
 
@@ -365,7 +365,6 @@ void midi_synth_render(int16_t* buf, int len)
 
 void midi_event_enqueue_byte(struct midi_serial_regs* mrp, uint8_t val)
 {
-    mrp->in_midi_last_command = 0;
     if (mrp->mfsz >= 256) return;
     mrp->midi_event_fifo[mrp->mfsz++] = val;
 }
@@ -434,8 +433,17 @@ int handle_midi_event(void* data, fluid_midi_event_t* event)
             val = dl_fluid_midi_event_get_program(event);
             midi_event_enqueue_short(mrp, cmd, val);
             break;
-        case MIDI_SYNC:
+        case MIDI_TIME_CODE:
+            val = dl_fluid_midi_event_get_value(event);
+            midi_event_enqueue_short(mrp, type, val);
+            mrp->in_midi_last_command = 0;
+            break;
         case MIDI_TUNE_REQUEST:
+            midi_event_enqueue_byte(mrp, type);
+            mrp->in_midi_last_command = 0;
+            break;
+        case MIDI_SYNC:
+        case MIDI_TICK:
         case MIDI_START:
         case MIDI_CONTINUE:
         case MIDI_STOP:
@@ -614,6 +622,7 @@ void midi_serial_step(int clocks)
             pthread_mutex_unlock(&mregs[sel].fifo_mutex);
             mregs[sel].clock += 0x1000000LL;
         }
+        midi_serial_iir_check(sel);
     }
 }
 
@@ -916,3 +925,10 @@ void midi_serial_write(uint8_t reg, uint8_t val)
             break;
     }
 }
+
+bool midi_serial_irq(void)
+{
+    bool uart0int = (mregs[0].iir & 1) == 0 && mregs[0].mcr_out2;
+    bool uart1int = (mregs[1].iir & 1) == 0 && mregs[1].mcr_out2;
+    return (uart0int | uart1int);
+}

src/midi.h

@@ -40,3 +40,4 @@ uint8_t midi_serial_read(uint8_t reg, bool debugOn);
 void midi_serial_write(uint8_t reg, uint8_t val);
 void midi_load_sf2(uint8_t* filename);
 void midi_synth_render(int16_t* buf, int len);
+bool midi_serial_irq(void);