@@ -49,7 +49,7 @@
 	bool (*init)(struct mCore*);
 	void (*deinit)(struct mCore*);
 
-	enum mPlatform (*platform)(struct mCore*);
+	enum mPlatform (*platform)(const struct mCore*);
 
 	void (*setSync)(struct mCore*, struct mCoreSync*);
 	void (*loadConfig)(struct mCore*, const struct mCoreConfig*);
@@ -90,12 +90,12 @@ void (*setKeys)(struct mCore*, uint32_t keys);
 	void (*addKeys)(struct mCore*, uint32_t keys);
 	void (*clearKeys)(struct mCore*, uint32_t keys);
 
-	int32_t (*frameCounter)(struct mCore*);
-	int32_t (*frameCycles)(struct mCore*);
-	int32_t (*frequency)(struct mCore*);
+	int32_t (*frameCounter)(const struct mCore*);
+	int32_t (*frameCycles)(const struct mCore*);
+	int32_t (*frequency)(const struct mCore*);
 
-	void (*getGameTitle)(struct mCore*, char* title);
-	void (*getGameCode)(struct mCore*, char* title);
+	void (*getGameTitle)(const struct mCore*, char* title);
+	void (*getGameCode)(const struct mCore*, char* title);
 
 	void (*setRTC)(struct mCore*, struct mRTCSource*);
 	void (*setRotation)(struct mCore*, struct mRotationSource*);
@@ -106,7 +106,7 @@ uint32_t (*busRead16)(struct mCore*, uint32_t address);
 	uint32_t (*busRead32)(struct mCore*, uint32_t address);
 
 	void (*busWrite8)(struct mCore*, uint32_t address, uint8_t);
-void (*busWrite16)(struct mCore*, uint32_t address, uint16_t);
+	void (*busWrite16)(struct mCore*, uint32_t address, uint16_t);
 	void (*busWrite32)(struct mCore*, uint32_t address, uint32_t);
 
 	uint32_t (*rawRead8)(struct mCore*, uint32_t address, int segment);

@@ -82,7 +82,7 @@ mCoreConfigFreeOpts(&core->opts);
 	free(core);
 }
 
-static enum mPlatform _GBCorePlatform(struct mCore* core) {
+static enum mPlatform _GBCorePlatform(const struct mCore* core) {
 	UNUSED(core);
 	return PLATFORM_GB;
 }
@@ -313,27 +313,27 @@ struct GBCore* gbcore = (struct GBCore*) core;
 	gbcore->keys &= ~keys;
 }
 
-static int32_t _GBCoreFrameCounter(struct mCore* core) {
-	struct GB* gb = core->board;
+static int32_t _GBCoreFrameCounter(const struct mCore* core) {
+	const struct GB* gb = core->board;
 	return gb->video.frameCounter;
 }
 
-static int32_t _GBCoreFrameCycles(struct mCore* core) {
+static int32_t _GBCoreFrameCycles(const  struct mCore* core) {
 	UNUSED(core);
 	return GB_VIDEO_TOTAL_LENGTH;
 }
 
-static int32_t _GBCoreFrequency(struct mCore* core) {
+static int32_t _GBCoreFrequency(const struct mCore* core) {
 	UNUSED(core);
 	// TODO: GB differences
 	return DMG_LR35902_FREQUENCY;
 }
 
-static void _GBCoreGetGameTitle(struct mCore* core, char* title) {
+static void _GBCoreGetGameTitle(const struct mCore* core, char* title) {
 	GBGetGameTitle(core->board, title);
 }
 
-static void _GBCoreGetGameCode(struct mCore* core, char* title) {
+static void _GBCoreGetGameCode(const struct mCore* core, char* title) {
 	GBGetGameCode(core->board, title);
 }
 

@@ -613,7 +613,7 @@ }
 	return true;
 }
 
-void GBGetGameTitle(struct GB* gb, char* out) {
+void GBGetGameTitle(const struct GB* gb, char* out) {
 	const struct GBCartridge* cart = NULL;
 	if (gb->memory.rom) {
 		cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
@@ -631,7 +631,7 @@ memcpy(out, cart->titleShort, 11);
 	}
 }
 
-void GBGetGameCode(struct GB* gb, char* out) {
+void GBGetGameCode(const struct GB* gb, char* out) {
 	memset(out, 0, 8);
 	const struct GBCartridge* cart = NULL;
 	if (gb->memory.rom) {

@@ -129,8 +129,8 @@ struct Patch;
 void GBApplyPatch(struct GB* gb, struct Patch* patch);
 
 bool GBIsROM(struct VFile* vf);
-void GBGetGameTitle(struct GB* gba, char* out);
-void GBGetGameCode(struct GB* gba, char* out);
+void GBGetGameTitle(const struct GB* gba, char* out);
+void GBGetGameCode(const struct GB* gba, char* out);
 
 void GBFrameEnded(struct GB* gb);
 

@@ -96,7 +96,7 @@ mCoreConfigFreeOpts(&core->opts);
 	free(core);
 }
 
-static enum mPlatform _GBACorePlatform(struct mCore* core) {
+static enum mPlatform _GBACorePlatform(const struct mCore* core) {
 	UNUSED(core);
 	return PLATFORM_GBA;
 }
@@ -329,26 +329,26 @@ struct GBACore* gbacore = (struct GBACore*) core;
 	gbacore->keys &= ~keys;
 }
 
-static int32_t _GBACoreFrameCounter(struct mCore* core) {
-	struct GBA* gba = core->board;
+static int32_t _GBACoreFrameCounter(const struct mCore* core) {
+	const struct GBA* gba = core->board;
 	return gba->video.frameCounter;
 }
 
-static int32_t _GBACoreFrameCycles(struct mCore* core) {
+static int32_t _GBACoreFrameCycles(const struct mCore* core) {
 	UNUSED(core);
 	return VIDEO_TOTAL_LENGTH;
 }
 
-static int32_t _GBACoreFrequency(struct mCore* core) {
+static int32_t _GBACoreFrequency(const struct mCore* core) {
 	UNUSED(core);
 	return GBA_ARM7TDMI_FREQUENCY;
 }
 
-static void _GBACoreGetGameTitle(struct mCore* core, char* title) {
+static void _GBACoreGetGameTitle(const struct mCore* core, char* title) {
 	GBAGetGameTitle(core->board, title);
 }
 
-static void _GBACoreGetGameCode(struct mCore* core, char* title) {
+static void _GBACoreGetGameCode(const struct mCore* core, char* title) {
 	GBAGetGameCode(core->board, title);
 }
 

@@ -742,7 +742,7 @@ }
 	return true;
 }
 
-void GBAGetGameCode(struct GBA* gba, char* out) {
+void GBAGetGameCode(const struct GBA* gba, char* out) {
 	memset(out, 0, 8);
 	if (!gba->memory.rom) {
 		return;
@@ -752,7 +752,7 @@ memcpy(out, "AGB-", 4);
 	memcpy(&out[4], &((struct GBACartridge*) gba->memory.rom)->id, 4);
 }
 
-void GBAGetGameTitle(struct GBA* gba, char* out) {
+void GBAGetGameTitle(const struct GBA* gba, char* out) {
 	if (gba->memory.rom) {
 		memcpy(out, &((struct GBACartridge*) gba->memory.rom)->title, 12);
 		return;

@@ -173,8 +173,8 @@
 bool GBAIsROM(struct VFile* vf);
 bool GBAIsMB(struct VFile* vf);
 bool GBAIsBIOS(struct VFile* vf);
-void GBAGetGameCode(struct GBA* gba, char* out);
-void GBAGetGameTitle(struct GBA* gba, char* out);
+void GBAGetGameCode(const struct GBA* gba, char* out);
+void GBAGetGameTitle(const struct GBA* gba, char* out);
 
 void GBAFrameStarted(struct GBA* gba);
 void GBAFrameEnded(struct GBA* gba);