【ARM】UART串口与看门狗——第五篇

#define GPA1CON     *((unsigned int *)0x11400020)
#define ULCON2      *((unsigned int *)0x13820000)
#define UCON2       *((unsigned int *)0x13820004)
#define UBRDIV2     *((unsigned int *)0x13820028)
#define UFRACVAL2   *((unsigned int *)0x1382002c)
#define UTXH2       *((unsigned int *)0x13820020)
#define URXH2       *((unsigned int *)0x13820024)
#define UTRSTAT     *((unsigned int *)0x13820010)
void myputs(char * str)
{
    int i;
    for(i = 0;str[i] != '\0'; i++)
    {
        //要发送数据一定要发送缓存寄存器为空，看状态寄存器，第一位为1就为空
        while(UTRSTAT & 2 == 0); //等于0就一直在当前循环执行
        UTXH2 = str[i];
    }
}
void delay()//延时函数
{
    int i =0,j = 0;
    for(;i<1000000; i++)
    {
        for(;j < 1000000;j++);
    }
}
int main()
{
​
    //设置GPIO，引脚为UART模式,GPA1_0,GPA1_1
    GPA1CON = GPA1CON & 0xff | 0x22;
    char a;
    //设置帧协议格式
    ULCON2 = 3;
    //控制寄存器，工作---有输出、输入（发送 接收）
    UCON2 = UCON2 & ~(0xf) | 5;
​
    //2、波特率设置
    UBRDIV2 = 53;
    UFRACVAL2 = 4;
​
    while(1)
    {   
        myputs("接收数据成功\n");
        if( UTRSTAT & 1 != 0 ) //uart控制器接收到外部硬件的数据
        {
            UTXH2= URXH2; ; //返回数据内容
            delay();
        }
    }
​
    return 0;
}

#define WDTCON      *((unsigned int *)0x10060000)
#define WDTDAT      *((unsigned int *)0x10060004)
#define WDTCNT      *((unsigned int *)0x10060008)
//初始化 wdt看门狗
void wdt_time()
{
    //初始时钟频率100M hz
    
    //设置预分配 250
    WDTCON = WDTCON & ~(0xff<<8) | 249<<8;
​
    //设置固定分频 128
    WDTCON = WDTCON & ~(0x3<<3) | 0x3<<3;
    
    //设置复位
    WDTCON = WDTCON | 1;// WDTCON |= 1;
​
    //设置定时时间,----5s
    WDTDAT = 15625;//(存储定时时间)
    WDTCNT = WDTDAT;
​
    //启动看门狗
    WDTCON |= 1<<5;
}