dmainit.c

CHP 2 - Real-Time Digital Signal Processing: Implementations and Applications, Second Edition by Sen

// 
//  Project: Experiment 2.10.8 Use DMA - Chapter 2 
//  File name: dmaInit.c   
//  Function(s): dmaInit()    
//
//  Description: This function initializes the C55x DMA channle (dmaNum).
//
//  For the book "Real Time Digital Signal Processing: 
//                Implementation and Application, 2nd Ed"
//                By Sen M. Kuo, Bob H. Lee, and Wenshun Tian
//                Publisher: John Wiley and Sons, Ltd
//
//  Tools used: CCS v.2.12.07
//              TMS320VC5510 DSK Rev-C
//

#include "dma.h"

#pragma CODE_SECTION(dmaInit, ".text:example:dmaInit");

void dmaInit(short dmaNum, short *initPtr)
{
  short i;
  ioport volatile unsigned short *dmaRegPtr;
    
  dmaNum<<=5; // Select the correct DMA channel(0x20 apart for each channel)
  dmaRegPtr = (ioport volatile unsigned short*)(DMACH0_BASE+ dmaNum);
    
  // Initialize the DMA registers
  for (i=0; i<DMA_REGS; i++)    
  {
    *dmaRegPtr++ = *initPtr++; 
  }
}