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CX . ' p . JCXZ , CX . '. ' , , , - , . , . ' , . , JAE JGE , .

 

3. . CX

. LOOP, , CX. LOOP CX 1. CX , , , CX 0, LOOP . . 7.2, LOOP, 䳿, . 7.1 , . MOV CX 10. LOOP CX, 1 CX DX. JMP A20 LOOP ADD AX,01 INC AX ( AX 1). JMP, LOOP LOOP A20, . LOOP -128 +127 . , "Relative jump out of range" ( ). LOOP , .7.1, , COM-. DEBUG. CX , p AX, BX DX . 000B, 0042 0400. Q. LOOP - LOOPE ( LOOPZ) LOOPNE ( LOOPNZ). CX 1. LOOPE , CX (ZF=1). LOOPNE , CX (ZF=0).

 

4. .

ò ֲ: AND, OR, XOR, TEST, NOT

. AND, OR, XOR TEST - . ֳ ASCII (..13). ', CF, OF, PF, SF, ZF.

AND: 1, 1; - 0.

OR: 1, 1; 0, - 0.

XOR: 0, 1, 1; ( - 0 - 1) - 0.

TEST: 䳺 AND- , .

' , . AND,OR XOR :

 

AND OR XOR

0101 0101 0101

0011 0011 0011

: 0001 0111 0110

 

' , , AL 1100 0101, BH 0101 1100:

 

1. AND AL,BH; AL 0100 0100

2. OR BH,AL; BH 1101 1101

3. XOR AL,AL; AL 0000 0000

4. AND AL,00; AL 0000 0000

5. AND AL,0FH; AL 0000 0101

6. OR CL,CL; SF ZF

 

3 4 . 5 AL. CMP , OR :

 

1. OR CX,CX; CX

JZ;,

2. OR CX,CX; CX

JS...;,

 

TEST 䳺 AND, , . :

 

1. TEST BL,11110000B; BL

JNZ...; ?

2. TEST AL,00000001B; AL

JNZ...; ?

3. TEST DX,OFFH; DX

JZ...; ?

 

NOT , ': , - . , , p AL 1100 0101, NOT AL 0011 1010. . NOT NEG, - , (." " .1.).

˲

, ', :

- ;

- ';

- ;

- 8 ( ) 16 ( );

- ( ) ( ).

1 c , 1 CL.





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