我买的是友善的mini2440的板子，自带的非操作系统的test的程序。在LIB.C中有个Delay的函数
void Delay(int time)
{
U32 val = (PCLK>>3)/1000-1;
rTCFG0 &= ~(0xff<<8);
rTCFG0 |= 3<<8; //prescaler = 3+1
rTCFG1 &= ~(0xf<<12);
rTCFG1 |= 0<<12; //mux = 1/2
rTCNTB3 = val;
rTCMPB3 = val>>1; // 50%
rTCON &= ~(0xf<<16);
rTCON |= 0xb<<16; //interval, inv-off, update TCNTB3&TCMPB3, start timer 3
rTCON &= ~(2<<16); //clear manual update bit
while(time--) {
while(rTCNTO3>=val>>1);
while(rTCNTO3<val>>1);
};
}
请问哪位大侠能指点一下这WHILE 里面的两个WHILE是什么意思吗？还有延迟具体多长时间？
