前两天写RTC中断 使用串口输出
发现程序会出现while(!(rUTRSTAT0 & 0x2));出不来的情况,但是中断是正常运作的
解决方法:
main函数增加:
U32 mpll_val = 0,consoleNum;
Port_Init(); //定义在2440lib.c
mpll_val = (92<<12)|(1<<4)|(1);
//init FCLK=400M,
ChangeMPllValue((mpll_val>>12)&0xff, (mpll_val>>4)&0x3f, mpll_val&3); (定义在2440lib.c)
ChangeClockDivider(14, 12); //the result of rCLKDIVN [0:1:0:1] 3-0 bit (定义在2440lib.c)
cal_cpu_bus_clk(); //HCLK=100M PCLK=50M
consoleNum = 0; // Uart 1 select for debug.
Uart_Init( 0,115200 ); // 定义在2440lib.c
Uart_Select( consoleNum ); // 定义在2440lib.cstatic U32 UPLL; static U32 cpu_freq;
void cal_cpu_bus_clk(void)
{
U32 val;
U8 m, p, s;
val = rMPLLCON;
m = (val>>12)&0xff;
p = (val>>4)&0x3f;
s = val&3;
//(m+8)*FIN*2 不要超出32位数!
FCLK = ((m+8)*(FIN/100)*2)/((p+2)*(1<<s))*100;
val = rCLKDIVN;
m = (val>>1)&3;
p = val&1;
val = rCAMDIVN;
s = val>>8;
switch (m) {
case 0:
HCLK = FCLK;
break;
case 1:
HCLK = FCLK>>1;
break;
case 2:
if(s&2)
HCLK = FCLK>>3;
else
HCLK = FCLK>>2;
break;
case 3:
if(s&1)
HCLK = FCLK/6;
else
HCLK = FCLK/3;
break;
}
if(p)
PCLK = HCLK>>1;
else
PCLK = HCLK;
if(s&0x10)
cpu_freq = HCLK;
else
cpu_freq = FCLK;
val = rUPLLCON;
m = (val>>12)&0xff;
p = (val>>4)&0x3f;
s = val&3;
UPLL = ((m+8)*FIN)/((p+2)*(1<<s));
UCLK = (rCLKDIVN&8)?(UPLL>>1):UPLL;
}
2440裸机串口调试 while(!(rUTRSTAT0 & 0x2));问题,布布扣,bubuko.com
2440裸机串口调试 while(!(rUTRSTAT0 & 0x2));问题
原文:http://blog.csdn.net/muyang_ren/article/details/36181579