Question

dsp问题求教。这个程序看了好久不懂，求大神指教，在线等

void processBuffer(void)
{
Uint32 addr;
static Int16 pingPong = PING;
Int16 i,gBuffer0[BUFFSIZE/2],gBuffer1[BUFFSIZE/2],gBuffer2[BUFFSIZE/2],gBuffer3[BUFFSIZE/2];

while(DMA_FGETH (hDmaRcv, DMACCR, ENDPROG)){
;
}

// Determine which ping-pong state we're in
if (pingPong == PING)
{
// Configure the receive channel for pong input data
addr = ((Uint32)gBufferRcvPong) << 1;
DMA_RSETH(hDmaRcv, DMACDSAL, addr & 0xffff);
DMA_RSETH(hDmaRcv, DMACDSAU, (addr >> 16) & 0xffff);

// Set new state to PONG
pingPong = PONG;
}
else
{
// Configure the receive channel for ping input data
addr = ((Uint32)gBufferRcvPing) << 1;
DMA_RSETH(hDmaRcv, DMACDSAL, addr & 0xffff);
DMA_RSETH(hDmaRcv, DMACDSAU, (addr >> 16) & 0xffff);

// Set new state to PING
pingPong = PING;
}

DMA_FSETH (hDmaRcv, DMACCR, ENDPROG, 1);
// DMA_FSETH (hDmaXmt, DMACCR, ENDPROG, 1);

if (pingPong == PONG)
{
//Insert your application program here
copyData(gBufferRcvPing, gBufferRcvPing, BUFFSIZE);
for(i=0;i<BUFFSIZE/2;i++)
{
gBuffer0[i]=gBufferRcvPing[2*i];
gBuffer1[i]=gBufferRcvPing[2*i+1];
}

fir(gBuffer0, h, gBuffer0, dbptr, NE, NH);
fir(gBuffer1, h, gBuffer1, dbptr, NE, NH);

for(i=0;i<BUFFSIZE/2;i++)
{
gBufferXmtPing[2*i]=gBuffer0[i];
gBufferXmtPing[2*i+1]=gBuffer1[i];
}
// Configure the transmit channel for ping output data
addr = ((Uint32)gBufferXmtPing) << 1;
DMA_RSETH(hDmaXmt, DMACSSAL, addr & 0xffff);
DMA_RSETH(hDmaXmt, DMACSSAU, (addr >> 16) & 0xffff);

}
else
{
//Insert your application program here
copyData(gBufferRcvPong, gBufferRcvPong, BUFFSIZE);
for(i=0;i<BUFFSIZE/2;i++)
{
gBuffer2[i]=gBufferRcvPong[2*i];
gBuffer3[i]=gBufferRcvPong[2*i+1];
}

fir(gBuffer2, h, gBuffer2, dbptr, NE, NH);
fir(gBuffer3, h, gBuffer3, dbptr, NE, NH);

for(i=0;i<BUFFSIZE/2;i++)
{
gBufferXmtPong[2*i]=gBuffer2[i];
gBufferXmtPong[2*i+1]=gBuffer3[i];
}
// Configure the transmit channel for pong output data
addr = ((Uint32)gBufferXmtPong) << 1;
DMA_RSETH(hDmaXmt, DMACSSAL, addr & 0xffff);
DMA_RSETH(hDmaXmt, DMACSSAU, (addr >> 16) & 0xffff);
}

// Start the DMA
// DMA_start(hDmaRcv);
// DMA_start(hDmaXmt);

}

Answer 1

大概看了下 应该是用DMA实现乒乓缓存
以下是我猜的哈
while循环等待 DMA中断 或者DMA寄存器状态改变
然后DMA配置重置
下面的程序是对DMA搬得数进行乒乓缓存
然后开启DMA继续搬数

具体DMA搬数的方式和地址要看DMA的配置