32 bit registers of PC proccesors

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bunalmis

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16 Bit AX register has two 8 bit parts. These are AH and AL.

AX is low 16 bit part of 32 Bit EAX register.

What is high 16 bit parts of EAX name ?

High 16 bit part of EAX can be break to two parts again same as AH,AL?
 

I don't think u can separate and use the higher bits of the EAX. i have had this problem b4, so i just ANDed the register contents by XXXX0000,(where XXXX is the bit-contents that u want preserved) so that the lower 16 bits would be reset, and the higher 16 bits would be whatever item u wanted.
give it a try.
 

No name, because pentium not support direct code to the high word of eax...edx, eg.
mov ax, 77ff -> mov ah, 77 / mov al, ff
but
mov eax, 7777ffff -> mov eah, 7777(not exist) / mov ax, ffff
the mov eah,7777 not supported by CPU
If you want to use it, you must shift it to low first.
shr eax, 16
mov [...], ax
 

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