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

Carlos Fenollosa пре 10 година
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1 измењених фајлова са 4 додато и 2 уклоњено
  1. 4 2
      08-32bit-print/README.md

+ 4 - 2
08-32bit-print/README.md

@@ -4,14 +4,16 @@ memory*
 **Goal: Print on the screen when on 32-bit protected mode**
 **Goal: Print on the screen when on 32-bit protected mode**
 
 
 32-bit mode allows us to use 32 bit registers and memory addressing, 
 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)
 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
 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
 at address `0xb8000` and it has a text mode which is useful to avoid
 manipulating direct pixels.
 manipulating direct pixels.
 
 
+
 The formula for accessing a specific character on the 80x25 grid is:
 The formula for accessing a specific character on the 80x25 grid is:
 
 
 `0xb8000 + 2 * (row * 80 + col)`
 `0xb8000 + 2 * (row * 80 + col)`