stm32串口1,2,3,4,5为什么不工作？

shyinyang · 发表于 2013-1-10 09:51:01

UART3和SPI2有冲突，要把SPI的时钟关掉。

仔细分析程序，最有可能的就是rcc了，我把她们全都打开了，结果我逐一调试，发现
RCC_APB1Periph_I2C1，RCC_APB1Periph_I2C2打开导致usart3不正常，RCC_AHBPeriph_SDIO打开导致usart4不正常，想的可能是管脚冲突，打开管教定义，呵呵，的确如此。

usart1是APB2，USART2,3,UART4,5都是APB1的，这个不会搞错的。

一般来说，代码要处理一下几部分内容：
1）RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_UART4, ENABLE);

2）NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);
NVIC_InitStructure.NVIC_IRQChannel = UART4_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

3）/* Configure UART4 Rx (PC.11) as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOC, &GPIO_InitStructure);

/* Configure UART4 Tx (PC.10) as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOC, &GPIO_InitStructure);

4）USART_InitStructure.USART_BaudRate = 115200;
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;

5）USART_Init(UART4, &USART_InitStructure);
/* Enable USART4 Receive and Transmit interrupts */
USART_ITConfig(UART4, USART_IT_RXNE, ENABLE);
/* Enable the USART4 */
USART_Cmd(UART4, ENABLE);

stm32串口1,2,3,4,5为什么不工作？