LPC1788---串口设置

LPC1788学习之串口学习-寄存器操作

接收数据使用中断接收---发送暂时是直接发送--简单的寄存器操作-记下不忘记！

#include "uart_lpc1788.h"


uint32_t Receive_Sign; //接收数据下标--接收数据个数
uint8_t  Receive_Buf[UART_RING_BUFSIZE]; //接收数组


/*-----------------------串口0初始化------------------*/
void Uart0_Init(uint32_t clk, uint32_t baudrate)
{
    uint32_t tmp;
    uint16_t divisorInt;


    LPC_IOCON->P0_2=0X21;
    LPC_IOCON->P0_3=0X21;


    LPC_SC->PCONP |= (1<<3); //外设时钟使能
//---------------------------------------------
    LPC_UART0->FCR=0X07;
    LPC_UART0->FCR=0X00;
    while (LPC_UART0->LSR & 0X01)
    {
        tmp = LPC_UART0->RBR;  //假读取去清空
    }
    LPC_UART0->TER = 0x80;
    while (!(LPC_UART0->LSR & 0x20));
    LPC_UART0->TER = 0;
    LPC_UART0->IER = 0;
    LPC_UART0->LCR = 0;
    LPC_UART0->ACR = 0;
    LPC_UART0->RS485CTRL = 0;
    LPC_UART0->RS485DLY = 0;
    LPC_UART0->ADRMATCH = 0;
    tmp = LPC_UART0->LSR;  //获取线状态寄存器
//-------------------------------------
    divisorInt =Uart0GetDivisorByBaudrate(clk,baudrate);   
    LPC_UART0->LCR |= 0x80; //使能访问除数寄存器

    LPC_UART0->DLM = (divisorInt>>8) & 0xFF;
    LPC_UART0->DLL = divisorInt & 0xFF;


    LPC_UART0->LCR &= (~0x80) & 0xFF; //禁止访问
//------------------------------------------
    tmp = (LPC_UART0->LCR & (0x80 | 0x40)) & 0xFF;
    tmp |= 0x03;  //8位数据-1个停止位-禁止奇偶校验
    LPC_UART0->LCR = (uint8_t)(tmp & 0xFF);
//----------------------------------------------
    tmp=0;
    tmp |= 0x01; //使能FIFO
    tmp |= 0x00; //触发点0-一个字符触发中断
    tmp |= 0x04; //发送缓存
    tmp |= 0x02; //接收缓存
    LPC_UART0->FCR = tmp & 0xFF;
//------------------------------------------------
    LPC_UART0->TER |= 0x80;//发送使能


    LPC_UART0->IER|= 0x01& 0x307; //使能RD数据接收中断
    LPC_UART0->IER|= 0x04& 0x307;  //使能RX线状态中断
//----------------------------------------------------
    Receive_Sign=0; 
//--------------------------------------
    NVIC_SetPriority(UART0_IRQn, ((0x01<<3)|0x01));
    NVIC_EnableIRQ(UART0_IRQn);
}
/*-------------------串口0中断函数----------------------*/
void UART0_IRQHandler(void)
{
    uint32_t  tmp, tmp1;


    tmp = ((LPC_UART0->IIR) & 0x3CF) & (7<<1);   //获取中断标识


    if (tmp == (3<<1)) //线状态中断
    {
        tmp1 = ((LPC_UART0->LSR) & 0xFF);
        tmp1 &= ((1<<1) | (1<<2) | (1<<3)| (1<<4) | (1<<7));
        if (tmp1)  //有错误
        {
            while (1){}
        }
    }
    if ((tmp == (2<<1)) || (tmp == (6<<1)))//接收数据中断--超时中断
    {
        Receive_Buf[Receive_Sign]= (LPC_UART0->RBR & 0xFF);  //读取数据
        Receive_Sign++;
    }
    if (tmp == (1<<1))//THRE发送中断
    {
        //UART_IntTransmit(); //发送数据--未使用
    }
}
/*-----------发送指定数组----------------*/
void UART0_SendStr(uint8_t *txbuf)
{
    uint8_t *pChar = txbuf;


    while(*pChar!='\0')
    {
        while (!(LPC_UART0->LSR & (1<<5)));//发送保持寄存器为空
        LPC_UART0->THR = (*pChar) & 0xFF; //发送数据
        pChar++;
    }
}
/*---------发送指定数组的指定长度-----不知道为啥-buflen不能使用sizeof函数----------*/
void UART0_SendStrNum(uint8_t *txbuf,uint32_t buflen)
{
    uint16_t i;
    uint8_t *pChar = txbuf;


    for(i=0;i    {
        while (!(LPC_UART0->LSR & (1<<5)));//发送保持寄存器为空
        LPC_UART0->THR = (*pChar) & 0xFF; //发送数据
        pChar++;
    }
}

/*----------根据外设频率与波特率计算分频寄存器的值----------*/
uint16_t Uart0GetDivisorByBaudrate(uint32_t clk, uint32_t baudrate)
{
    float divisor;
    uint16_t divisorInt;
    
    divisor = (float)clk/(baudrate*16);    
    divisorInt = (uint16_t)(divisor/256);    
    divisor-=(divisorInt*256);
    
    if ((divisor - (uint32_t)divisor) > 0.5F)  //四舍五入
    {
        divisorInt = (divisorInt << 8) | ((uint8_t)divisor + 1);
    }
    else
    {
        divisorInt = (divisorInt << 8) | (uint8_t)divisor;
    }    
    return divisorInt;  //高8位-DLM--低8位-DLL

}