Detecting Memory (x86): Difference between revisions
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Put back the old code after reading RBIL on the matter. |
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Usage: |
Usage: |
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<source lang="asm"> |
<source lang="asm"> |
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; Nullify the A-register. |
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xor ax, ax |
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; Switch to the BIOS (= request low memory size). |
; Switch to the BIOS (= request low memory size). |
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int 0x12 |
int 0x12 |
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; The carry flag is set, it failed. |
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; AX = amount of continuous memory in KB starting from 0. |
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jc .Error |
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; Test the A-register with itself. |
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test ax, ax |
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; The zero flag is set, it failed. |
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jz .Error |
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; AX = amount of continuous memory in |
; AX = amount of continuous memory in KB starting from 0. |
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</source> |
</source> |
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Note: this function always works and may not modify the carry flag, so the contents of AX should be trusted and CF should be ignored. |
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Alternately, you can just use INT 0x15, EAX = 0xE820 (see below). |
Alternately, you can just use INT 0x15, EAX = 0xE820 (see below). |
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