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CAVITE STATE UNIVERSITY
T3 CAMPUS
Department of Information Technology COSC 65 – Programming Languages

; Sample code for AND Instruction RULE in AND SIZE: MUST BE THE SAME SIZE!
.model small Syntax: AND destination, source

.data
.code AND reg, reg ; register to another reg
main proc AND reg, memory ; register to memory
mov ah, 00000001b AND reg, immediate ; register to immediate
mov bh, 00000101b AND memory, reg ; memory to register
AND ah, bh AND memory, immediate ; memory to immediate
endp
end main Solution RULE for AND Instruction
1 AND 1 = 0
00000001b 1 AND 0 = 1
00000101b 0 AND 1 = 1
00000001b -> answer 0 AND 0 = 0

; Sample code for OR Instruction RULE in OR SIZE: MUST BE THE SAME SIZE!

.model small Syntax: OR destination, source
.data
.code OR reg, reg ; register to another reg
main proc OR reg, memory ; register to memory
mov ah, 00000001b OR reg, immediate ; register to immediate
mov bh, 00000101b OR memory, reg ; memory to register
OR ah, bh OR memory, immediate ; memory to immediate
endp
end main Solution RULE for AND Instruction
1 OR 1 = 1
00000100b 1 OR 0 = 1
00000011b 0 OR 1 = 1
00000111b -> answer 0 OR 0 = 0

; Sample code for XOR Instruction RULE in XOR SIZE: MUST BE THE SAME SIZE!

.model small Syntax: XOR destination, source
.data
.code XOR reg, reg ; register to another reg
main proc XOR reg, memory ; register to memory
mov ah, 00000001b XOR reg, immediate ; register to immediate
mov bh, 00000101b XOR memory, reg ; memory to register
XOR ah, bh XOR memory, immediate ; memory to immediate
endp
end main Solution RULE for XOR Instruction
1 OR 1 = 1
11111111b 1 OR 0 = 1
11111110b 0 OR 1 = 1
00000001b -> answer 0 OR 0 = 0

Note: You can use the single step process on emu8086 to check what’s happening on our code.

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