chunyang 发表于 2014-7-29 13:20 
从未听说模块有明显的波特率误差，一般都是发生在MCU端，主频不合适所致。 ...
#include "stm32f10x.h"
void GPIOInit(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); //使能PA端口时钟
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);
/*
GPIO_InitStructure.GPIO_Pin = \
GPIO_Pin_3;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
*/
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); //使能PB端口时钟
GPIO_InitStructure.GPIO_Pin = \
GPIO_Pin_6 | GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9 \
| GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
PB6=PB7=PB8=PB9=0;
PB12=PB13=PB14=PB15=0;
}
void serial1_init(void){
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
USART_InitTypeDef USART_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA|RCC_APB2Periph_AFIO, ENABLE);
//USART1_TX PA.9
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);
//USART1_RX PA.10
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
//Usart1 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1; //
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
USART_InitStructure.USART_BaudRate = 19200;
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);
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
USART_Cmd(USART1, ENABLE);
USART_ClearFlag(USART1,USART_FLAG_TC);
}
char buff[256];
char *p;
void USART1_IRQHandler(void) //串口1中断服务程序
{
u8 c;
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)
{
//USART_ClearITPendingBit(USART1, USART_IT_RXNE);
c = USART_ReceiveData(USART1);//(USART1->DR);
*p++ = c;
}
}
int main(void){
GPIOInit();
serial1_init();
p = buff;
while(1){
if(*p=='\n'){
printf(buff);
memset(buff,0,sizeof(buff));
p = buff;
}
}
return 0;
}
老大您说的没错，的确是这样，是我不够严谨，主观乱猜的，刚刚用逻辑分析仪看了一下模块输出时序的确没问题，这是我单片机的程序，单纯测串口接收是没问题的，只不过跟模块对接就会出现那种现象，实在解释不通，外部晶振8M，MCU是STM32F103C8T6
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