`ovl_first_game` OK (#108)

* c file

* match 3 funcs

* update

* rename sys_romcheck

* sys_romcheck NON_MATCHING

* match sys_romcheck

* notes

* fix

* review

2 files changed, 49 insertions, 0 deletions

diff --git a/src/overlays/gamestates/ovl_first_game/first_game.c b/src/overlays/gamestates/ovl_first_game/first_game.c
new file mode 100644
index 0000000..cf01443
--- /dev/null
+++ b/src/overlays/gamestates/ovl_first_game/first_game.c
@@ -0,0 +1,27 @@
+#include "first_game.h"
+#include "m_common_data.h"
+#include "67E840.h"
+#include "attributes.h"
+#include "overlays/gamestates/ovl_second_game/second_game.h"
+
+void exit_game(Game_FirstGame* this);
+void sys_romcheck(void);
+
+void exit_game(Game_FirstGame* this) {
+    sys_romcheck();
+    mBGM_ct();
+    common_data_init();
+
+    STOP_GAMESTATE(&this->state);
+    SET_NEXT_GAMESTATE(&this->state, second_game_init, sizeof(Game_SecondGame));
+}
+
+void first_game_cleanup(Game* thisx UNUSED) {
+}
+
+void first_game_init(Game* thisx) {
+    Game_FirstGame* this = (Game_FirstGame*)thisx;
+
+    thisx->destroy = first_game_cleanup;
+    exit_game(this);
+}
diff --git a/src/overlays/gamestates/ovl_first_game/sys_romcheck.c b/src/overlays/gamestates/ovl_first_game/sys_romcheck.c
new file mode 100644
index 0000000..684bf9c
--- /dev/null
+++ b/src/overlays/gamestates/ovl_first_game/sys_romcheck.c
@@ -0,0 +1,22 @@
+#include "first_game.h"
+#include "carthandle.h"
+#include "m_nmi_buf.h"
+#include "attributes.h"
+
+#define DEBUG_ROM_VERSION 0x23
+
+void sys_romcheck(void) {
+    u32 sp24;
+    u8 version;
+    UNUSED s32 pad;
+
+    // Read the last 4 bytes from the ROM header
+    osEPiReadIo(carthandle, 0x3C, &sp24);
+
+    version = sp24;
+    sp24 = DEBUG_ROM_VERSION;
+    // Check if the version byte is equal to DEBUG_ROM_VERSION
+    if (version == sp24) {
+        APPNMI_ZURUMODE2_SET();
+    }
+}