keil5中STM32F103使用RS485发送数组

在Keil5中使用STM32F103发送RS485数组，需要先配置串口和GPIO的相关参数，然后使用串口发送函数发送数据。下面给出一个简单的示例代码：

#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_usart.h"

#define RS485_DIR_PIN GPIO_Pin_8
#define RS485_DIR_PORT GPIOA

void USART_Configuration(void)
{
    USART_InitTypeDef USART_InitStructure;
    GPIO_InitTypeDef GPIO_InitStructure;

    // Enable clock for USART1 and GPIOA
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA, ENABLE);

    // Configure USART1 Tx (PA9) as alternate function push-pull
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    // Configure USART1 Rx (PA10) as input floating
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    // Configure RS485 direction control pin (PA8) as output push-pull
    GPIO_InitStructure.GPIO_Pin = RS485_DIR_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(RS485_DIR_PORT, &GPIO_InitStructure);

    // Configure USART1 for 115200 baud, 8 data bits, no parity, 1 stop bit
    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_Tx | USART_Mode_Rx;
    USART_Init(USART1, &USART_InitStructure);

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

void RS485_TxEnable(void)
{
    GPIO_ResetBits(RS485_DIR_PORT, RS485_DIR_PIN);
}

void RS485_RxEnable(void)
{
    GPIO_SetBits(RS485_DIR_PORT, RS485_DIR_PIN);
}

void USART_SendDataArray(USART_TypeDef* USARTx, uint8_t* data, uint16_t length)
{
    RS485_TxEnable(); // Enable RS485 transmission

    for (uint16_t i = 0; i < length; i++)
    {
        while (USART_GetFlagStatus(USARTx, USART_FLAG_TXE) == RESET);
        USART_SendData(USARTx, data[i]);
    }

    while (USART_GetFlagStatus(USARTx, USART_FLAG_TC) == RESET);

    RS485_RxEnable(); // Enable RS485 reception
}

int main(void)
{
    uint8_t data[4] = {0x12, 0x34, 0x56, 0x78};

    USART_Configuration();

    while (1)
    {
        USART_SendDataArray(USART1, data, sizeof(data));
        for (int i = 0; i < 1000000; i++); // Delay for 1 second
    }
}

在上面的代码中，我们首先定义了RS485方向控制引脚的GPIO端口和引脚号。然后在`USART_Configuration()`函数中，配置了USART1的相关参数，包括波特率、数据位、停止位、校验位等。同时也配置了RS485方向控制引脚的GPIO为输出模式。`USART_SendDataArray()`函数用于发送一个字节数组，其中先调用`RS485_TxEnable()`函数使能RS485发送，然后通过循环发送每个字节，最后再调用`RS485_RxEnable()`函数使能RS485接收。

在主函数中，我们定义了一个长度为4的字节数组`data`，然后通过`USART_SendDataArray()`函数发送该数组，每隔1秒钟发送一次。你可以将`data`数组替换成你需要发送的数组。