51单片机的汇编作业

1：
ORG 0000H
LJMP MAIN
ORG 0030H
MAIN:
MOV DPTR,#1000H
MOV R0，#30H
LP:
MOVX A,@DPTR
MOV @R0,A
CLR A
MOVX @DPTR,A
INC DPTR
INC R0
CJNE R0,#60H,LP
SJMP $
END
2:
ORG 0000H
LJMP MAIN
ORG 0030H
MAIN:
MOV DPTR,#2000H
MOV R2,#0 ;正
MOV R3,#0 ;负
MOV R4,#0 ;零
MOV R7,#100
LP:
MOVX A,@DPTR
JNZ LP1
INC R4
SJMP LPC
LP1:
JB ACC.7,LP2
INC R2
SJPM LPC
LP2:
INC R3
LPC:
DJNZ R7,LP
SJMP $
END
3:
ORG 0000H
LJMP MAIN
ORG 0030H
MAIN:
MOV TMOD,#20H
MOV TH1,#0F3H
MOV TL1,#0F3H
SETB TR1
MOV SCON,#0C0H
MOV R0,#30H
MOV R2,#10
LP:
MOV A,@R0
MOV C,P
MOV TB8,C
MOV SBUF,A
JNB TI,$
CLR TI
DJNZ R2,LP
SJMP $
END