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lessons 8, 9, 10, entering 32-bit mode

Carlos Fenollosa 10 years ago
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      08-32bit-print/README.md

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08-32bit-print/README.md

@@ -4,14 +4,16 @@ memory*
 **Goal: Print on the screen when on 32-bit protected mode**
 
 32-bit mode allows us to use 32 bit registers and memory addressing, 
-protected memory, virtual memory and other advangades, but we will lose
+protected memory, virtual memory and other advantages, but we will lose
 BIOS interrupts and we'll need to code the GDT (more on this later)
 
-In this lesson we will write a print string routine by directly manipulating
+In this lesson we will write a new print string routine which works in
+32-bit mode, where we don't have BIOS interrupts, by directly manipulating
 the VGA video memory instead of calling `int 0x10`. The VGA memory starts
 at address `0xb8000` and it has a text mode which is useful to avoid
 manipulating direct pixels.
 
+
 The formula for accessing a specific character on the 80x25 grid is:
 
 `0xb8000 + 2 * (row * 80 + col)`