51??????????/??????
???80C51???/??????
???/????????????????????????????乤???????䴙???????÷????????????????????????????????????????????????????????????????/?????????????????????в????????????
(??) ???/???????????????
?? ???/??????????????TCON
(1) TCON.7 TF1???????1??????λ?????????1??????????????????????????TF1=1?????ж??????????CPU?????????1???ж?????????ж??????????????????0?????ж????????TF1????????????????????????????0??
(2) TCON.6 TR1???????1???п???λ??????????1????0??????????????1????GATE=1????INT1????????TR1??1?????????1;??GATE=0???TR1??1?????????????1??
(3) TCON.5 TF0???????0??????λ???书???????????TF1??
(4) TCON.4 TR0???????0???п???λ???书???????????TR1??
(5)??????????ж??????
?? ???/?????????????????????TMOD
?? M1M0 ???? ??????????λ
?? C/T ???? ????/?????????λ
C/T=1,???????????,??????????????,????????????
C/T=0,??????????,???????????????,???????????
?? GATE ???? ???λ
GATE=0?????????TCON?????п???λTR0/TR1??????
GATE=1??????????TR0/TR1?????ж??????????????????е?INT0/INT1=1??TR0/TR1=1,T0/T1???????С?
TMOD?????89H,????λ????,????TMOD????????????䶮
(??). ???/?????????????
?? ???????0
13λ??????????TL0??5λ??TH0?? 8λ????TL0??5λ???????????TL0??6λ??λ????????TH0??λ??13λ?????????TF0?á?1???????????213 = 8192??
????????TH0=(8192-5000)/32;TL0=(8192-5000)%32;????5ms???????12M????
?? ???????1
16λ????????????????216 = 65536??
????????TH0=(65536-50000)/256;TL0=(65536-50000)%256;????50ms???????12M????
?? ???????2
8λ????????????TL0??????????????28= 256???????????????????????TF0 = 1;??????棬???????TH0?е??????TL0??
?????????????????;?????????ΧС??
????????????????????????Χ???????ó????
????????TH0=TL0=256-200????200us???????12M????
?? ???????3
???3????????T0??T1????3??
?? T0???3
????3?????,T0??????????????8λ??????TH0??TL0??
?? TL0???T0??е???????????:TF0,TR0,GATE,C/T,INT0,??????8λ????/??????;
?? TH0????T1???ж???????TF1,???п??????TR1,?????????????????,????????8λ?????(??????????????)??
?? T0???3??????T1
T1??????TF1??TR1??T0??TH0?????????????????????????????????п???????????п?????????????
(??)?????/???????????
?? ?????/????????????????????
(1) ??????????????????????TMOD????????
(2) ????????????
(3) ????????????ж??????
(4) ?????????
1. ?????/??????????趨????
(1)???????????????????
(2)?????/???????
80C51???/??????????????
????: N????????й?: ???0?,N=13;???1?,N=16;???2??3?,N=8??
?????????????????й?:???????=12/fosc??fosc=12MHZ???1????=1mS; fosc=6MHZ ???1????=2mS??
??????????????????/????????????????????
????admin ?????????2018-05-18
