Question

我试图从终端发送AT命令认为USART1，然后使用USART2到GSM调制解调器[终端 - ＆gt; USART1 - ＆gt; USART2 - ＆gt;调制解调器]。发送AT命令后，调制解调器不会发回任何东西。可能是什么问题？ USART1工作正常。我正在使用STM32 Nucleo和Keil uVision4。

发送功能

void send_usart2(char *msg){
send_usart1("USART2 sending...");   send_usart1("\r\n");
while (*msg){
    while(USART_GetFlagStatus(USART2, USART_FLAG_TXE) == RESET);
    USART_SendData(USART2, *msg++);
    }
    send_usart1("USART2 sending successful");   send_usart1("\r\n");
}

USART2处理程序

void USART2_IRQHandler(void){
int index = 0;
if(USART_GetITStatus(USART2, USART_IT_RXNE) != RESET){
    USART_ClearITPendingBit(USART2, USART_IT_RXNE);
    Received_values[index++] = USART_ReceiveData(USART2);
    }
}

中断初始化

void InitInterrupt2(void) {
NVIC_InitTypeDef NVIC_InitStruct2;                             
NVIC_InitStruct2.NVIC_IRQChannel = USART2_IRQn;
NVIC_InitStruct2.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStruct2.NVIC_IRQChannelSubPriority = 0;           
NVIC_InitStruct2.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStruct2);
}

UART初始化

void InitUART2(void) {      
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

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);         /* Configure USAR1 */                    
USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
USART_Cmd(USART2,ENABLE);                       /* Enable the USART1 */                                             

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; 
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
//GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}

这看起来就像我发送的那样。

    .....
    send_usart2(Command_buffer);                
    send_usart1("Command: ");
    send_usart1(Command_buffer);
    send_usart1("\r\n");    
    memset(Command_buffer, NULL, sizeof(Command_buffer));
    os_dly_wait(500);
    send_usart1("Received values: ");
    send_usart1(Received_values);
    send_usart1("\r\n");
    memset(Received_values, NULL, sizeof(Received_values));
    .......

Answer 1

我需要配置此行格式：

USART_HardwareFlowControl = USART_HardwareFlowControl_None;

要：

USART_HardwareFlowControl = USART_HardwareFlowControl_RTS;

这意味着USART2和调制解调器需要“握手”连接类型。

使用USART2发送AT命令到GSM调制解调器[嵌入式C]

1 个答案: