看了USART1的教程,参照着写了USART2的发送,但是,串口助手接收到的是不断发送过来的00,特向各位求解,不知是不是有什么没注意到的。用的是ISO-MINI的开发板
配置 USART2 代码如下:
void USART2_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
/* config USART2 clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
/* USART2 GPIO config */
/* Configure USART2 Tx (PA.2) as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure USART2 Rx (PA.3) as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* USART2 mode config */
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;
USART_Init(USART2, &USART_InitStructure);
USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
USART_Cmd(USART2, ENABLE);
}
int fputc(int ch, FILE *f)
{
USART_SendData(USART2, (uint8_t) ch);
while (USART_GetFlagStatus(USART2, USART_FLAG_TC) == RESET);
return (ch);
}
int main(void)
{
/* USART2 config 115200 8-N-1 */
USART2_Config();
printf("\r\n this is a usart printf demo \r\n");
for(;;)
{
}
}
用串口助手无法收到数据。 |