ClearPending(BIT_DMA2);
rINTMOD = 0x0;
// initialize philips UDA1341 chip
init_1341(PLAY);
// set BDMA interrupt
pISR_DMA2 = (unsigned)dma2_done;
rINTMSK &= ~(BIT_DMA2);
// initialize variables
f_nDMADone = 0;
//DMA2 Initialize
rDISRCC2 = (0<<1) + (0<<0); //AHB, Increment
rDISRC2 = ((INT32T)(pWavFile));
rDIDSTC2 = (1<<1) + (1<<0); //APB, Fixed
rDIDST2 = ((INT32T)IISFIFO); //IISFIFO
rDCON2 = (1<<31)+(0<<30)+(1<<29)+(0<<28)+(0<<27)+(0<<24)+(1<<23)+(0<<22)+(1<<20)+nSoundLen/2;
//Handshake, sync PCLK, TC int, single tx, single service, I2SSDO, I2S request,
//Auto-reload, half-word, size/2
rDMASKTRIG2 = (0<<2)+(1<<1)+0; //No-stop, DMA2 channel on, No-sw trigger
//IIS Initialize
//Master,Tx,L-ch=low,iis,16bit ch.,CDCLK=384fs,IISCLK=32fs
rIISCON = (1<<5)+(0<<4)+(0<<3)+(1<<2)+(1<<1);
rIISMOD = (0<<8) + (2<<6) + (0<<5) + (0<<4) + (1<<3) + (1<<2) + (1<<0);
rIISPSR = (2<<5) + 2; //Prescaler_A/B=3
//Tx DMA enable,Rx DMA disable,Tx not idle,Rx idle,prescaler enable,stop
rIISFCON = (1<<15) + (1<<13); //Tx DMA,Tx FIFO --> start piling....
rIISCON |= 0x1; // enable IIS
while( f_nDMADone == 0);
rINTMSK |= BIT_DMA2;
rIISCON = 0x0; // IIS stop
void __irq dma2_done(void)
{
ClearPending(BIT_DMA2); // clear pending bit
f_nDMADone = 1;
}
不懂为什么一到while( f_nDMADone == 0); 程序就跑飞呢？ |
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