4.1 4.2

4.1

4.1.1 MASMKeil C51 4.1.2

4.1.3

1. [] ORG 16 2. [] END

3. EQU EQU

4. DATA

EQU1EQUDATA2EQUDATA3DATA

5. [] DB 8 8

6. [] DW 16 16

7. [] DS DBDWDS

8. BIT BIT

4.2 4.2.1

1 2 3 4

89C514

[] [] []

$

4.2.2 . MCS-51 MOVC A, @A+DPTR MOVC A, @A+PC

4.1C = a2 + b2 abcRAMDADBDC A A

SQR1: INC A MOVC A,@A+PC RET TAB: DB 0, 1, 4, 916 DB 2536496481

START1: MOV A,DAH ACALL SQR1 MOV R1,A a2 (R1) MOV A,DBH ACALL SQR1 b2 (A) ADD A,R1 a2+b2 (A) MOV DCH,A SJMP $

SQR2:PUSH DPH PUSH DPL MOV DPTR,#TAB MOVC A,@A+DPTR POP DPL POP DPH RET TAB: DB 0, 1, 4, 91625 DB 36496481

4.21ASCII ADELMXZXAXDXEXLXMXXXZ

1.TAB5:DB A DW XA DB D DW XD DB E DW XE DB L DW XLDB MDW XMDB XDW XXDB ZDW XZDB 0

2)A LTB5: MOV DPTR#TAB5 MOV BA LOP5: CLR A MOVC A@A+DPTR JZ LEND INC DPTR CJNE A,B,LNF5 CLR A DPTR

MOVC A,@A+DPTR MOV B,A ; B INC DPTR CLR A MOVC A,@A+DPTR ; A MOV DPL,A MOV DPH,B CLR A JMP @A+DPTR ;

LNF5:INC DPTR INC DPTR SJMP LOP5LEND: . . .

MCS-51 JMP @A+DPTR

4.3128

1R300H7FHJMP1: MOV A, R3 RL A 2 A MOV DPTR, #JMPTAB JMP @A+DPTR +2JMPTAB: AJMP ROUT00 AJMP ROUT01 . . AJMP ROUT7F

2 1128 < N < 256 2R3 JMP2: MOV DPTR,#TBL9 MOV A,R3 ADD A,R3 (R32 A JNC NADD INC DPH (R32256

NADD: MOV R2,A MOVC A,@A+DPTR XCH A,R2 8 (R2) INC A MOVC A,@A+DPTR 8 A MOV DPL,A MOV DPH,R2 CLR A JMP @A+DPTR

TBL9: DW PRG0 DW PRG1 . . DW PRGn

3RET 1> n255 2> (R3R2) JMP3: MOV DPTR,#TBL10 MOV A,R2 2 CLR C RLC A XCH A,R3 RLC A ADD A,DPH 2 +DPH MOV DPH,A DPH

MOV A,R3 2 AMOVC A,@A+DPTR R3XCH A,R3INC DPTRMOVC A,@A+DPTR APUSH AMOV A,R3PUSH ARET PC

TBL10: DW PRG0 DW PRG1 . . DW PRGn

4.4: 8BCDHUNDTENONE HUND DATA 20H TENONE DATA 21H BINBCD: MOV B,#100 DIV AB A/100, MOV HUNDA MOV AB MOV B#10

DIV AB /10 SWAP A A ADD AB MOV TENONEA RET

4.5 ASCII

ASCII ASCII 1. ASCII=4=10+37H

BINASCMOV A R2 ANL A#0FH 4 PUSH A CLR C SUBB A#0AH POP A JC LOOP

4.6BCD1>16, (N)D= a15215 + a14 214 +.+ a0 20 =((((a15 2)+a14) 2+a13) 2+) 2+a0 2>

3BTOD2MOV R1 DADR BCD R1 MOV R2 BYTE INC R2 R2 CLR ABBO MOV @R1A BCD INC R1 DJNZ R2BBO MOV ABYTE R3) MOV B#08H MUL AB MOV R3A

BB3MOV R0BADR R0 MOV R2BYTE CLR CBB1MOV A@R0 RLC A CY MOV @R0A INC R0 DJNZ R2BB1 MOV R2BYTE INC R2 MOV R1DADR

BB2MOV A@R1 BCD2 ADDC A@R1 DA A MOV @R1A INC R1 DJNZ R2BB2 DJNZ R3BB3 RET

4.7:

R0= R1= R2= R0=

ADDBIN CLR C LOOP1: MOV A,@R0 ADDC A,@R1 MOV @R0,A INC R0 INC R1

DJNZ R2,LOOP1 JNC LOOP2 MOV @R0,#01H RET LOOP@: DEC R0 RET

4.8

R0= R1= R2= R0= R3= 07H =

SUBBIN PUSH PSW CLR C CLR 07H MOV R3#00H LOOP3 MOV A@R0 SUBB A@R1 MOV R0A INC R0 INC R1 INC R3

DJNZ R2LOOP3 JNB CYLOOP4 SETB 07H 1LOOP4POP PSW CY RET

4.9: a,b => R7R6 c,d => R5R4 4 => RAM @R0,@(R0+1), @(R0+2),@(R0+3)1 2

4-2

3 MUL: MOV A,R6 b (A) MOV B,R4 d (B) MUL AB bd MOV @R0,A bdL @R0 MOV R3,B bdH (R3) MOV A,R4 ad (B,A) MOV B,R7 MUL AB ADD A,R3 MOV R3,A bdH + adL (R3) MOV A,B

ADDC A,#00H adH + Cy (R2)MOV R2,AMOV A,R6 cb (B,A)MOV B,R5MUL ABADD A,R3 bdH + adL + bcL @(R0+1)INC R0MOV @R0,AMOV R1,#00HMOV A,R2 adH + bcH + Cy (R2)ADDC A,BMOV R2,A

JNC LAST INC R1 R1LAST:MOV A,R7 ac (B,A) MOV B,R5 MUL AB ADD A,R2 adH + bcH + acL @(R0+2) INC R0 MOV @R0,A MOV A,B acH + Cy @(R0+3) ADDC A,R1 INC R0 MOV @R0,A RET

4.10 4 => R2R3R4R5 2 => R6R7 2 => R4R5 2 => R2R31 2

(R2R3)>?(R6R7)N16B0CYR2R3R4R5CYCF0(R2R3)(R6R7)AR1F0=?1NC=?1(AR1)(R2R3 ) (R5+1)R5(1)(B)-1=?0Y0F0NY 1F0Y Y N4-3

3 NDIV1:MOV A,R3 CLR C SUBB A,R7 MOV A,R2 SUBB A,R6 JNC NDVE1 ;R2R3)>(R6R7), MOV B,#16 ( R2R3)

MOV R5,AMOV A,R4RLC AMOV R4,AMOV A,R3RLC AMOV R3,AXCH A,R2RLC AXCH A,R2MOV F0,CCLR C

SUBB A,R7 MOV R1,A MOV A,R2 SUBB A,R6 JB F0,NDVM1 F0=1 JC NDVD1 F0=0CY=1 NDVM1:MOV R2,A MOV A,R1 MOV R3,A INC R5 1.

NDVD1:DJNZ B,NDVL1 0 CLR F0 SJMP $NDVE1:SETB F0 SJMP $

1. 2. a b c d