GPIO_Mode_IN_FLOATING

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我是靠谱客的博主矮小热狗，最近开发中收集的这篇文章主要介绍GPIO_Mode_IN_FLOATING，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

#include "stm32f10x.h"
	#include "stm32f10x_conf.h"

	int main(void)
	{
	GPIO_InitTypeDef GPIO_InitStructure;
	USART_InitTypeDef USART_InitStructure;

	uint16_t rxbuf[64];
	int rxbuf_pos = 0;
	int i;

	/* Enable peripheral clocks for USART1 on GPIOA */
	RCC_APB2PeriphClockCmd(
	RCC_APB2Periph_USART1 \|
	RCC_APB2Periph_GPIOA \|
	RCC_APB2Periph_AFIO, ENABLE);

	/* Configure PA9 and PA10 as USART1 TX/RX */

	/* PA9 = alternate function push/pull output */
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	/* PA10 = floating input */
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	/* Configure and initialize usart... */
	USART_InitStructure.USART_BaudRate = 9600;
	USART_InitStructure.USART_WordLength = USART_WordLength_8b;
	USART_InitStructure.USART_StopBits = USART_StopBits_1;
	USART_InitStructure.USART_Parity = USART_Parity_No;
	USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
	USART_InitStructure.USART_Mode = USART_Mode_Rx \| USART_Mode_Tx;

	USART_Init(USART1, &USART_InitStructure);

	/* Enable USART1 */
	USART_Cmd(USART1, ENABLE);

	while (1)
	{
	/* Wait until there's data in the receive data register */
	while (USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET);

	/* Read a byte */
	rxbuf[rxbuf_pos++] = USART_ReceiveData(USART1);

	/* Check if the previous byte was a newline */
	if ((rxbuf[rxbuf_pos-1] == 'n' \|\| rxbuf[rxbuf_pos-1] == 'r') && rxbuf_pos != 0) {

	/* Send the line back */
	for (i = 0; i < rxbuf_pos; i++) {
	USART_SendData(USART1, rxbuf[i]);

	/* Wait until the byte has been transmitted */
	while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
	}

	rxbuf_pos = 0;
	}
	}
	}