lesson 16, kprint

16-video-driver/drivers/screen.h

@@ -0,0 +1,14 @@
+#define VIDEO_ADDRESS 0xb8000
+#define MAX_ROWS 25
+#define MAX_COLS 80
+#define WHITE_ON_BLACK 0x0f
+#define RED_ON_WHITE 0xf4
+
+/* Screen i/o ports */
+#define REG_SCREEN_CTRL 0x3d4
+#define REG_SCREEN_DATA 0x3d5
+
+/* Public kernel API */
+void clear_screen();
+void kprint_at(char *message, int col, int row);
+void kprint(char *message);