本人学习STM32是直接通过操作stm32的寄存器,使用的开发板是野火ISO-V2版本; 先简单的介绍一下stm32的GPIO; stm32的GPIO有多种模式: 1.输入浮空 2.输入上拉 3.输入下拉 4.模拟输入 5.开漏输出 6.推挽式输出 7.推挽式复用功能 8.开漏复用功能 stm32GPIO模式设置相关寄存器设置的介绍
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stm32中文参考手册中对GPIO模式设置对应寄存器的详细介绍:6 M$ W! ?: k' y6 S& g3 ]
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下图为开发板LED的接线图; $ ~' C8 f1 w& D! k# \" _
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根据上面的电路图可知,将GPIOB_0,GPIOF_7和GPIOF_8设置为低电平时,LED将被点亮; 程序代码: LED.h 文件 - #ifndef __LED_H
: \' L) c9 \" I, L2 a) T - #define __LED_H" R8 {3 i' N& u
1 Y1 f; E( `" V3 a" o) X" k- void GPIO_Init(void); S: P! Z. V5 @" d6 }
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stm32.h 文件 0 f L, _2 x- t5 Z5 M
- #ifndef __STM32_H, t! M, n8 A! L. b
- #define __STM32_H# `# P; `5 ]- r/ J% C; n
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- //引脚寄存器定义4 Y4 e! R& _1 t
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- //GPIO对应寄存器起始地址* z3 Y/ A7 y4 G0 O
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- #define GPIOA 0x40010800$ x4 Y7 P4 Y: Q
- #define GPIOB 0x40010C00
4 [9 r+ B& z% k, ~" e- e - #define GPIOC 0x40011000+ p$ o2 u6 l" Y3 A
- #define GPIOD 0x40011400% p% q. l" {* e! Q
- #define GPIOE 0x40011800) [$ A0 M6 S' } T( H) U% B# J, y* e
- #define GPIOF 0x40011C00! e3 v2 u8 v9 d. P0 j4 I( j) L
- #define GPIOG 0x40012000 F; T5 J4 P, @) a ~/ p* i
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- //寄存器偏移地址
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- #define GPIOx_CRL 0x00
) x- K H( D; ?; N6 i - #define GPIOx_CRH 0x04
" o6 ]; i- B$ y) U - #define GPIOx_IDR 0x087 `6 P+ ~; U) B$ W3 |* Y
- #define GPIOx_ODR 0x0c
. z# @( E+ M& @0 z, _* N; ^$ N - #define GPIOx_BSRR 0x10) h: `; n2 b4 @# o4 Z8 d7 a3 k
- #define GPIOx_BRR 0x14
4 ^# S6 X t( \& N: L# x3 i - #define GPIOx_LCKR 0x184 x+ E- u3 @: w- h
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- #define GPIOB_CRL *((volatile unsigned int *)(GPIOB + GPIOx_CRL))
$ Y% X6 {8 ^' j- G' d: J% Y% s7 W - #define GPIOB_CRH *((volatile unsigned int *)(GPIOB + GPIOx_CRH))
/ a- \, g& v6 L4 p - #define GPIOB_IDR *((volatile unsigned int *)(GPIOB + GPIOx_IDR))
8 I! x X% J1 d6 x - #define GPIOB_ODR *((volatile unsigned int *)(GPIOB + GPIOx_ODR))4 J8 ~8 k' W- t
- #define GPIOB_BSRR *((volatile unsigned int *)(GPIOB + GPIOx_BSRR))4 Q" ~+ L' ~5 E" q, u
- #define GPIOB_BRR *((volatile unsigned int *)(GPIOB + GPIOx_BRR))$ M, k( R5 G! c+ j! I+ U& U
- #define GPIOB_LCKR *((volatile unsigned int *)(GPIOB + GPIOx_LCKR))1 v T% a. P. y! L9 K
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- #define GPIOF_CRL *((volatile unsigned int *)(GPIOF + GPIOx_CRL)) c/ m+ V6 [/ ?- C7 K- B1 S; K
- #define GPIOF_CRH *((volatile unsigned int *)(GPIOF + GPIOx_CRH))
1 ^/ x4 a5 F W( Q& ? - #define GPIOF_IDR *((volatile unsigned int *)(GPIOF + GPIOx_IDR))2 U' S1 D4 i) \; S5 V
- #define GPIOF_ODR *((volatile unsigned int *)(GPIOF + GPIOx_ODR))
8 ]5 e+ {; n8 p. A/ C% O - #define GPIOF_BSRR *((volatile unsigned int *)(GPIOF + GPIOx_BSRR))4 x- Z7 y/ _. f( a" ~
- #define GPIOF_BRR *((volatile unsigned int *)(GPIOF + GPIOx_BRR))
* Y. o8 p! Q% U' K/ J- ]- {% H - #define GPIOF_LCKR *((volatile unsigned int *)(GPIOF + GPIOx_LCKR))
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- #endif
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LED.c 文件 - #include "LED.h"9 e& E) `5 |, m$ i! K1 Q( e
- #include "stm32.h"* J# v; p9 Q: U8 o5 A4 k) J
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- void delay(unsigned int x)! I! @' S) j B% G7 |" H R# p
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- volatile int i, j;" b1 l$ W1 E1 A- [* ]* t* w
- for(i = 0; i < x; i++)
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7 b9 P6 L; _5 j2 w# L- L- void GPIO_Init(void)
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/ }, Z$ N1 w2 S. }, ~* L( W - //使能GPIOB和GPIOF的时钟9 U9 ~% E, D6 m0 ]5 c
- RCC_APB2ENR |= 1 << 3;0 W3 P' ~7 X/ g1 Y) `8 S
- RCC_APB2ENR |= 1 << 7;9 ]* j' h. e( X0 Q3 s/ j; G
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- //清除GPIOB和GPIOF的配置寄存器
! }5 U1 d9 \" H: B) h4 X$ U - GPIOB_CRL &= ~(0xf << 0);
+ [2 J7 Y/ l1 V" _/ X3 [ - GPIOF_CRL &= ~(0xf << 0);
" u* q2 h( d7 }. U+ r6 V - GPIOF_CRH &= ~(0xf << 0);+ g; X5 }, T7 Z! P. F' x. Z$ B* i( t
1 t; E& G; V# L6 s0 }# w0 I1 A- //配置GPIOB和GPIOF的端口为通用推挽输出,输出速度为50HZ3 q# T0 e+ d( l2 y6 ~
- GPIOB_CRL |= 3 << 0;
0 @5 x( I" C. P/ D3 v# z - GPIOF_CRL |= 3 << 28;
$ t0 L2 B* s% A2 q; D# X/ \ - GPIOF_CRH |= 3 << 0;
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- //设置GPIOB_0和GPIOF_7和GPIOF_8输出为高电平! w" s" z. D. }; T- V% q
- GPIOB_ODR |= 1 << 0;
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- int main(void)
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- GPIO_Init();4 m$ `3 T) ~+ u; B& j
8 E6 u6 d1 ^- R5 K6 {; a. Z* j- GPIOB_ODR &= ~(1 << 0); //设置GPIOB_0端口输出为低电平
8 x' Z* [' h8 e+ ], @! f - GPIOF_ODR &= ~(3 << 7); //设置GPIOF_7和GPIOF_8输出为低电平( R6 f9 [# ~& j) _, i) c* n
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- GPIOB_ODR &= ~(1 << 0); //设置GPIOB_0端口输出为低电平6 e# w/ o+ `. Y
- GPIOF_ODR |= 3 << 7; //设置GPIOF_7和GPIOF_8输出为高电平
4 x2 g: H5 H7 U$ z/ j9 J! Y - delay(100);4 I! O- z: ]; m2 W4 n
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- GPIOB_ODR |= 1 << 0; //设置GPIOB_0端口输出为高电平
# y" |& m( ?$ }) B - GPIOF_ODR &= ~(1 << 7); //设置GPIOF_7输出为低电平% W: H9 \0 b3 V% N* ]: R4 U: Y4 I0 I
- delay(100);$ A8 l/ Z6 F$ Q* W5 V9 o
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- GPIOF_ODR &= ~(1 << 8); //设置GPIOF_7输出为高电平
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- delay(100);
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程序将实现流水灯的效果; 在使用GPIO时一定要将相应GPIO的时钟开启; 0 N) H* s8 _1 O) }5 Y* H
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