Question
Calculate the changes in AX and CF for each of the instruction in the program below (Assume initial CF=0)
MOV AX, F0h
SHL AH,3
SAR AH,4
RCR AH,1
OR AH,AL
Answer
MOV AX, F0h
--> AX = 0000 0000 | 1111 0000
--> CF = 0
SHL AH,3
--> AH = 0000 0000 , shift to left 3 times will equal to 0000 0000 (no changes)
--> AX = 0000 0000 | 1111 0000
--> CF = 0
SAR AH,4
--> AH = 0000 0000 , shift arithmetic to right 3 times will make AH equal to 0000 0000 (no changes)
--> AX = 0000 0000 | 1111 0000
--> CF = 0
RCR AH,1
--> AH = 0000 0000 , shift with carry to right 1 times will make AH equal to 0000 0000 (no changes) and CF equal to zero
--> AX = 0000 0000 | 1111 0000
--> CF = 0
OR AH,AL
--> AH = 0000 0000
--> AL = 1111 0000
--> OR AH,AL --> AH = AH OR AL = 1111 0000 (F0h) --> AX = F0F0h , CF = 0
ROL AL,3
--> AL=11110000, rotate to left 3 times will make AL equal to 1000 0111 (87h)
--> AX = F087h, CF=1
Bila dunia didagangkan
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Alangkah indahnya... jika dunia dapat diperdagangkan untuk akhirat... bila
setiap rezeki diletakkan kembali kepada jalan yang hak.. bila setiap rezeki
yg h...
11 years ago
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