Need help on answering these 3 questions for my assembly language class. 1. Writ

Question

Need help on answering these 3 questions for my assembly language class.

1. Write an instruction that performs a bitwise or on the contents of the 32 bit D register and and the 32 bit A register and places the result in the D register.

2. Which registers are changed by the following instruction when executed? Assume AL is FF and BL is 00.

A. ADD AL,BL

AL, BL, EDI

BL, EIP

AL, EIP

AL, BL, EIP, EFL

AL, AX, EAX, EIP, EFL

3. Write an instruction that performs a bitwise or on the contents of the CH register and and the AL register and places the result in the AL register.

AL, BL, EDI

BL, EIP

AL, EIP

AL, BL, EIP, EFL

AL, AX, EAX, EIP, EFL

Explanation / Answer

(1). The instruction that performs a bitwise or on the contents of the 32 bit D register and and the 32 bit A register and places the result in the D register.

      OR EDX, EAX        ; The EDX = EDX 0r EAX, the reslt of the bit wise OR operation on EAX and EDX is stored in EDX

          The EAX and EDX are repersents 32-bit rgisters

(2).      AL = FF h = 1111 1111 (in binary)

           BL = 00 h = 0000 0000 (in binary)

ADD AL,BL     ; This instruction function is, the addition of AL and BL result is stored in to the AL register

After excution of any instruction EIP will change because it is 32-bit instruction pointer and it points next instruction memory address but here after adding of AL (FF h) to BL (00 h) there is no effect on their contents here.

For General after addition AL and EIP will change

(3). The instruction that performs a bitwise or on the contents of the CH register and and the AL register and places the result in the AL register.

        OR AL, CH ; Here AL = AL or CH, The result of OR operation on AL and CH are stored in AL register

Related Questions

Navigate

• Browse (All)
• Browse N
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.