谁会单片机的计数器编程

你向用计数器做什么？给你一个例程
ORG 000H
AJMP START
ORG 001BH
JMP SERVICE
START:
MOV A,#0FEH
MOV R1,#00H
MOV P1,#0FEH
MOV TMOD,#10H
MOV TH1,#00H
MOV TL1,#30H
SETB EA
SETB ET1
SETB TR1
WAIT: JMP WAIT
SERVICE:
MOV TH1,#00H
MOV TL1,#10H
CLR TF1
CJNE R1,#00H,RRL
RLL:
RL A
MOV P1,A
CJNE A,#0F7H,RETUN
MOV R1,#01H
RETUN: RETI
RRL:
MOV P1,A
RR A
CJNE A,#07FH,RETUN
MOV R1,#00H
RETI
END