Figure 1 -- Physical Address Translation

   
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+-----------------------------------------------+
|                                               |
| Address:  8123:FFEC                           |
|                                               |
|   +-------+-------+                           |
|   | 8123  |       | X 16                      |
|   +-------+-------+                           |
|   | 81230 | 0FFEC | + 16-bit offset           |
|   +-------+-------+                           |
|   | 9121C |         Physical address          |
|   +-------+                                   |
|                                               |
| (a) Real mode addressing                      |
|                                               |
+-----------------------------------------------+
|                                               |
| Address:  0058:FFEC                           |
|             |                     GDT         |
|             |                +-----------+    |
|             |                | No entry  |  0 |
|             |                +-----------+    |
|             |                | Base Addr |  8 |
|             |                +-----------+    |
|             |                | Base Addr | 10 |
|             |                +-----------+    |
|             |                | Base Addr | 18 |
|             |                +-----------+    |
|             |                   . . . .       |
|             |                   . . . .       |
|             |                   . . . .       |
|             |                +-----------+    |
|             |                | Base Addr | 50 |
|             +----->---->---->+-----------+    |
|                              | Base Addr | 58 |
|       +-<----<----<----<-----+  =81230   |    |
|       |                      +-----------+    |
|       |                         . . . .       |
|       |                         . . . .       |
|       |                         . . . .       |
|   +-------+-------+                           |
|   | 81230 | 0FFEC | + 16-bit offset           |
|   +-------+-------+                           |
|   | 9121C |         Physical address          |
|   +-------+                                   |
|                                               |
| (b) Protected mode addressing                 |
|                                               |
+-----------------------------------------------+

   
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