STM32???GPIO???
GPIO:
STM32??(64?????)IO???????3?????????PA??PB??PC.
STM32??IO???????????????ó?8??????
1????????
2??????????
3??????????
4?????????
5????????
6?????????
7???????ù???
8????????ù???
STM32?????IO??????7???????????????????????????????2??32λ???????ü????CRL??CRH;2??32λ??????????IDR??ODR;1??32λ????λ/??λ?????BSRR;???16λ???λ?????BRR;1??32λ??????????LCKR;????????IO??????????4????CRL??CRH??IDR??ODR??
???(??????STM32?????????κ???????????????????!APB2ENR??APB2?????????????????????)
1.CRL??CRH?????-->????IO?????????????
STM32??CRL?????????IO???(A~G)???8λ????(????PA0-PA7)?????IO????λ???CRL??4??λ??????λ?CNF??????λ?MODE?????????????????????????????????0X4????????????(ADC??)??0X3????????????(??????????50M????)??0X8?????/??????????(?????????)??0XB??????????(???IO??????????50M????)??
STM32??CRH?????????IO???(A~G)???8λ????(????PA8-PA15)?????IO????λ???CRH??4??λ??????λ?CNF??????λ?MODE??
2.IDR???????ODR?????--??????????????????(????????????)??????????????????(????????????)
IDR????????????????????????????16λ???ü????????????????????????16λ??????????????????????IO???????
ODR????????????????????????????16λ???ü???????????д???????ü???????????????????0?????д????Ч???????????????????????
3. BSRR ???λ????/??????????BRR????λ?????
BSRR???????????????Щ????????????о????????á???????????????????????ú??????PA5???“1”????GPIOA->BSRR |=(1<<5);5????????????“0”????????
GPIO->BSRR |=(1<<(5+16));?????16??????????
??BRR??BSRR?????????
???ODR????PC????????????????ж????ж?IO??????(??????????PC3???ж?????PC6)????????ODR???????????????????????????????????????????GPIO??????????????????????????????????????ODR?????????BRR??BSRR?????IO?????????????????????????????
?ο???????BRR??BSRR?????????м??仰(??GPIO???????)??
“???I/O???λ??????????????I/0???????????32λ???????(?????????????????)??GPIOx_BSRR??GPIOx_BRR????????????κ?GPIO????????/????????????;???????????????????????IRQ???????Σ???”
“????GPIOx_ODR?????λ???????????????????ж???????APB2д??????????????????????λ???????????“??λ/??λ?????”(GPIOx_BSRR????λ?? GPIOx_BRR)??????????λд’1’??????????????λ???????????”
??????????????ж??????IO?????????????BSRR??BRR?????????????ODR.
????admin ?????????2018-05-18
