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Q39370: Addressing above 1 Megabyte |
/pubs/pc/reference/microsoft/kb/Q39370/ |
Article: Q39370
Version(s): 5.00 | 5.10
Operating System: MS-DOS | OS/2
Flags: ENDUSER | reference words
Last Modified: 12-JAN-1989
Question:
The 80286 is capable of addressing a maximum of 16 megabytes of
memory; however, with 16-bit segment and offset registers, I can only
reach 1 megabyte. How can I address this extra memory?
Response:
When the 80286 is in real mode, it is not possible to reach that
memory -- you are limited to 1 megabyte. To use that space, you have
to put the processor into protected mode by using IBM ROM BIOS Call -
Interupt 15 function 89h.
For more information about this interrupt, call IBM hardware support
at (800) 426-2468. This information is not covered in the DOS
Encyclopedia.