当前位置:文档之家› 第3章 80x86指令系统习题解答

第3章 80x86指令系统习题解答


0150H[BX], (10)SAR BYTE PTR 0150H[BX],1 =____, CF=____, (11350H) =____, CF=____, OF=____ 解:EA=BX+0150H=1350H PA= PA=DS*16+EA=11350H, (11350H)=0A5H= 10100101B 11010010B=0D2H, CF=1,OF=0 当移位数为1 最高位不变则OF=0) (当移位数为1是,最高位不变则OF=0) 0150H[BX], (11)SAL BYTE PTR 0150H[BX],1 (11350H)=____,CF=____, (11350H)=____,CF=____,OF=____ 解:EA=BX+0150H=1350H,PA=DS*16+EA=11350, (11350H)=0A5H= 10100101B 01001010B=4AH, CF=1,OF=1
3.4
阅读下列各小题的指令序列, 阅读下列各小题的指令序列,在后面空格中填入 该指令序列的执行结果。 该指令序列的执行结果。 BL, (1) MOV BL,85H MOV AL,17H AL, AL, ADD AL,BL DAA AL=____, BL=____, AL=____, BL=____, CF=____ 解:17H+85H=9CH AL 17H+85H= 压缩的BCD码加法十进制调整指令。 BCD码加法十进制调整指令 DAA 压缩的BCD码加法十进制调整指令。 (AL的低 的低4 >9或AF=1,ALAL+06H,AF (AL的低4位>9或AF=1,ALAL+06H,AF1; AF是辅助进位标志用以标志D3 D4的进位 是辅助进位标志用以标志D3向 AF是辅助进位标志用以标志D3向D4的进位 AL的高 的高4 >9或CF=1,ALAL+60H,CF1;) AL的高4位>9或CF=1,ALAL+60H,CF1;) AL=9CH+ 06H=0A2H 02H, AL=0A2H+60H=02H AL=0A2H+60H=02H, BL=85H CF=1
BX, (3)LEA BX,[BX+20H][SI] AX, MOV AX,[BX+2] 解:BX= BX+20H+ SI=0056H EA= BX+2=58H PA=DS*16+EA=91D0H+58H=9228H PA= AX=(09228H)=1E40H AX=(09228H)= (4) LDS SI,[BX][DI] MOV[SI], MOV[SI],BX PA=DS 解:EA= BX+DI=56H, PA= *16+EA=91D0H+56H =9226H SI=(09226H)=00F6H, DS=(09228H)=1E40H SI=00F6H, PA= *16+EA= PA=DS EA=1E400H+00F6H=1E4F6H EA= SI= (1E4F6H)= BX=0024H
BH, (7)SUB BH,0150H[BX][SI] BH=____,SF=____,ZF=____,PF=____,CF=____, BH=____,SF=____,ZF=____,PF=____,CF=____,0F=____ EA=0150H+BX+SI=26A4H; 解:EA=0150H+BX+SI=26A4H; PA=DS*16+EA=10000H+26A4H=126A4H; PA=DS*16+EA=10000H+26A4H=126A4H; (126A4H)=9DH,BH=12H BH=75H, SF=0,ZF=0,PF=0, CF=1 ,OF=0 (8)INC BYTE PTR 0152H[BX] (11352H)=____,(11353H)=____, (11352H)=____,(11353H)=____,CF=____ 解:EA=0152H+ BX= 1352H,PA=DS*16+EA=11352, (11352H)=0FFH, 不影响CF (11352H)=00H, (11353H)= 26H, 不影响CF (9)INC WORD PTR 0152H[BX] (11352H)=____,(11353H)=____, (11352H)=____,(11353H)=____,CF=____ 解:EA=0152H+ BX= 1352H, PA=DS*16+EA=11532, (11352H)=0FFH, (11353H)= 26H (11352H)=00H, (11353H)= 27H, 不影响 不影响CF
解: 补码为-19,IP目标 目标=IP源+2+EA(即-19) (1)E7补码为 ) 补码为 , 目标 源 ( ) =016EH+2-19=0157H 因为段内寻址,所以cs=2000H不变 因为段内寻址,所以 不变 目标=IP源+3 (2)IP目标 ) 目标 源 +EA=016EH+3+1600H=1771H 所以cs=2000H不变 因为段内寻址 所以 不变 所以cs=2000H不变 (3) IP=16C0H, 因为段内寻址 所以 ) 不变 (4)段间寻址,有机器码可看出 )段间寻址,有机器码可看出IP=0146H CS=3000H (5)段内寻址,所以 )段内寻址,所以CS=2000H不变 不变 DS*16+0072H+BX=61732H ,(61733H)=17H (61732H)=70H,( ) ,( ) IP=1770H (6)PA=DS*16+BX=60000H+16C0H=616C0H ) (616C0H)=46H (616C1H)=01H IP=0146H (616C2H)=00H (616C3H)=30H CS=3000H
(5)
CX, XCHG CX,[BX+32H] XCHG[BX+20H][SI], XCHG[BX+20H][SI],AX
பைடு நூலகம்
PA=DS 解:EA= BX+32H=56H, PA= *16+EA=91D0H+56H =9226H (09226H)= CX=5678H , CX=(09226H)=00F6H CX= BX+20H+SI=56H,PA=DS EA= BX+20H+SI=56H,PA= *16+EA=91D0H+56H =9226H AX=(09226H)=5678H ,(09226H) = AX=(09226H)=
AX=1234H
3.2设DS=1000H,SS=2000H,AX=1A2BH,BX=1200H,CX=339AH,BP=1200H,SP=1350H, 3.2设DS=1000H,SS=2000H,AX=1A2BH,BX=1200H,CX=339AH,BP=1200H,SP=1350H, SI=1354H,(11350H)=0A5H,(11351H)=3CH,(11352H)=0FFH,(11353H)=26H, SI=1354H,(11350H)=0A5H,(11351H)=3CH,(11352H)=0FFH,(11353H)=26H, (11354H)=52H,(11355H)=OE7H,(126A4H)=9DH,(126A5H)=16H,(21350H)=88H, (11354H)=52H,(11355H)=OE7H,(126A4H)=9DH,(126A5H)=16H,(21350H)=88H, (21351H)=51H 下列各指令都在此环境下执行,在下列各小题的空格中填入相应各指令的执行结果。 下列各指令都在此环境下执行,在下列各小题的空格中填入相应各指令的执行结果。
AX, (4) MOV AX,0150H[BP] AX=____ BP+0150H= 解:EA= BP+0150H=1350H PA=SS PA= *16+EA=20000H+1350H=21350H AX=5188H
AX=____, (5)POP AX ; AX=____,SP=____ 解:EA= SP=1350H PA=SS PA= *16+EA=20000H+1350H=21350H AX=5188H, SP=1350H+2H=1352H (6)ADD[SI], (6)ADD[SI],CX (11354H)=____,(11355H)=____, (11354H)=____,(11355H)=____,SF=____ ZF=____, PF=____, CF=____, ZF=____, PF=____, CF=____, OF=____ 解:EA=SI=1354H, PA=DS*16+EA=10000H+1354H=11354H (11354H)=52H, CX=339AH, (11354H)=52H,(11355H)=OE7H 0E752H+339AH=11AECH0E752H+339AH=11AECH->(11355H): (11354H) (11354H) =0ECH, (11355H)= 1AH
第三章习题讲评
3.1 已知DS=091DH,SS=1E4AH,AX=1234H,BX=0024H,CX=5678H,BP=0024H SI=0012H,DI=0032H,(09226H)=00F6H,(09228H)=1E40H,(1E4F6H)=091DH。 在以上给出的环境下,试问下列指令或指令段执行后的结果如何?
(11354H) =0ECH, (11355H)= 1AH CF=1,ZF=0, PF(低八位奇偶校验 低八位奇偶校验) PF(低八位奇偶校验):0ECH= 11101100B PF=0 SF(最高位状态 最高位状态) SF(最高位状态),1H=0001B SF=0 OF(溢出标志 溢出标志) OF(溢出标志) 0E752H= 0E752H=1110011101010010B 339AH=11001110011010B 1110011101010010 1110011101010010 + 11001110011010 10001101011101100
相关主题