STM32设置GPIO模式
1. 宏定义功能I2C软件模拟驱动(Bit-Banging),寄存器方式设置GPIO:
#define SDA_IN() {GPIOB->CRH&=0X0FFFFFFF;GPIOB->CRH|=(u32)8<<28;}
#define SDA_OUT() {GPIOB->CRH&=0X0FFFFFFF;GPIOB->CRH|=(u32)3<<28;}
此代码常见于I2C通过快速切换引脚方向实现双向数据传输:
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***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
优点:直接操作寄存器,切换速度快,适合实时性要求高的场景(如I2C位翻转)。
缺点:可读性较差,需熟悉寄存器位域定义。
2. 代码解析
(1) 基本概念
操作寄存器:GPIOB->CRH(控制GPIOB的Pin8~Pin15)。
移位操作:x << n, 将x向左移动n位
引脚确定:操作的是 Pin15(因为每引脚占4位,28 = 7×4,对应Pin15的配置位)。
(2) 寄存器操作逻辑
GPIOB->CRH &= 0X0FFFFFFF:0x0FFFFFFF = 0000 1111 1111 1111 1111 1111 1111 1111
将CRH寄存器的位(Pin15的CNF15和MODE15)清零,保留其他引脚配置
GPIOB->CRH |= (u32)8<<28: 8<<28 = 1000 0000 0000 0000 0000 0000 0000 0000
CNF15 = 10:浮空输入模式; MODE15 = 00:输入无需速度配置。
GPIOB->CRH |= (u32)3<<28:3<<28 = 0011 0000 0000 0000 0000 0000 0000 0000
CNF15 = 00:推挽输出模式; MODE15 = 11:输出速度50MHz
(3) HAL库等效代码
若使用STM32 HAL库,等效代码如下:
// SDA_IN(): 浮空输入
GPIO_InitTypeDef GPIO_InitStruct = {0};
GPIO_InitStruct.Pin = GPIO_PIN_15;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;// 浮空输入
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
// SDA_OUT(): 推挽输出,50MHz
GPIO_InitStruct.Pin = GPIO_PIN_15;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_50MHz;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
注意事项
时钟使能:操作前需确保GPIOB时钟已启用(RCC->APB2ENR |= RCC_APB2ENR_IOPBEN)。
引脚冲突:避免与其他外设(如SPI、TIM)复用引脚时配置冲突。
位域安全:在多任务环境中,操作寄存器需加锁或关中断防止竞态条件。
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版权声明:本文为CSDN博主「bing_feilong」的原创文章,遵循CC 4.0 BY-SA版权协议,转载请附上原文出处链接及本声明。
原文链接:https://blog.csdn.net/bing_feilong/article/details/149941459
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