x86 assembly Guru's?

Discussion in 'BIOS Mods' started by Darth_nVader, Dec 19, 2009.

  1. Darth_nVader

    Darth_nVader MDL Novice

    Nov 17, 2009
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    #1 Darth_nVader, Dec 19, 2009
    Last edited by a moderator: Apr 20, 2017
    Would someone be so kind as to help me understand this bit of code:

    Code:
      mov ecx,0x17
    rdmsr
    test eax,0x8000 
    jnz 0xb430
    clc
    mov edx,eax
    and dx,0x1f1f
    mov bh,dh
    
    Does the test eax,0x8000 test to see if bit 15 = 1?
     
  2. secr9tos

    secr9tos MDL Addicted

    Jul 28, 2009
    999
    133
    30
    So it does not only check bit 15...
     
  3. andyp

    andyp SLIC Tools Author

    Aug 8, 2008
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    #3 andyp, Dec 22, 2009
    Last edited by a moderator: Apr 20, 2017