What would be in registers ax, ah and al after these commands:
MOV AX, 1010
MOV AH, 5
ADD AL, 5
I understand that ax contains ah and al but I don't know the answer of this question
Srcee
0
Junior Poster in Training
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Jump to PostYou can type in the code using DEBUG at the DOS command-line and step through each command and watch the registers.
C:\science>debug -a 1424:0100 mov ax, 1010 1424:0103 mov ah, 5 1424:0105 add al, 5 1424:0107 -r AX=0000 BX=0000 CX=0000 DX=0000 SP=FFEE BP=0000 SI=0000 DI=0000 DS=1424 ES=1424 …
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thines01
401
Postaholic
Team Colleague
Featured Poster
You can type in the code using DEBUG at the DOS command-line and step through each command and watch the registers.
C:\science>debug
-a
1424:0100 mov ax, 1010
1424:0103 mov ah, 5
1424:0105 add al, 5
1424:0107
-r
AX=0000 BX=0000 CX=0000 DX=0000 SP=FFEE BP=0000 SI=0000 DI=0000
DS=1424 ES=1424 SS=1424 CS=1424 IP=0100 NV UP EI PL NZ NA PO NC
1424:0100 B81010 MOV AX,1010
-p
AX=1010 BX=0000 CX=0000 DX=0000 SP=FFEE BP=0000 SI=0000 DI=0000
DS=1424 ES=1424 SS=1424 CS=1424 IP=0103 NV UP EI PL NZ NA PO NC
1424:0103 B405 MOV AH,05
-p
AX=0510 BX=0000 CX=0000 DX=0000 SP=FFEE BP=0000 SI=0000 DI=0000
DS=1424 ES=1424 SS=1424 CS=1424 IP=0105 NV UP EI PL NZ NA PO NC
1424:0105 0405 ADD AL,05
-p
AX=0515 BX=0000 CX=0000 DX=0000 SP=FFEE BP=0000 SI=0000 DI=0000
DS=1424 ES=1424 SS=1424 CS=1424 IP=0107 NV UP EI PL NZ NA PO NC
1424:0107 0000 ADD [BX+SI],AL DS:0000=CD
-q
C:\science>
thines01
401
Postaholic
Team Colleague
Featured Poster
So, you can see that the AX register contains 0515
AH=05 AL=15
Srcee
0
Junior Poster in Training
Thank you :)
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