document splash_screen.h (#331)

include/splash_screen.h

@@ -1,14 +1,38 @@
+/**
+ * @file splash_screen.h
+ *
+ * @brief Functions and constants for the splash screen intro
+ *
+ */
 #ifndef SPLASH_SCREEN_H
 #define SPLASH_SCREEN_H
 
 #include <tonc.h>
 
+/** @name Splash screen timing variables
+ *
+ *  Constants for timing the duration of the splash screen.
+ *
+ * @{
+ */
 #define SPLASH_FPS              60
 #define SPLASH_DURATION_SECONDS 10
 #define SPLASH_DURATION_FRAMES  (SPLASH_FPS * SPLASH_DURATION_SECONDS)
+/** @} */
 
-void splash_screen_on_init();
-void splash_screen_on_update();
-void splash_screen_on_exit();
+/**
+ * @brief Initialize the splash screen by printing the splash screen text.
+ */
+void splash_screen_on_init(void);
+
+/**
+ * @brief Update splash screen timers and print the remaining time accordingly.
+ */
+void splash_screen_on_update(void);
+
+/**
+ * @brief Exit the splash screen
+ */
+void splash_screen_on_exit(void);
 
 #endif // SPLASH_SCREEN_H