spi.c

Arm 控制ad9954源程序

/*------------------------------------------------------------
  FILE NAME : spi.c
DESCRIPTION : spi driver.
VERSION     : 0.1.0
AUTHOR      : 
CREATE DATE : 2.13.2008
MODIFY DATE : 
LOGS        :
--------------------------------------------------------------*/


//--------------------Include files-----------------------//
#include "..\header\ad9954.h"

//-------------------Function prototype-------------------//
void SendData (unsigned char data);
//-------------Function area--------------------------//
/*---------------------------------------------------------------
NAME       : Delay_NS(dly)
ENTRY  TYPE: void
RETURN TYPE: int
DESCRIPE    : funtion for time delay
-----------------------------------------------------------------*/
void Delay_NS (unst32 dly)
{  int i;
   for(;dly>0;dly--){
     for(i=0;i<5000;i++);
	 }
	 
}

/*--------------------------------------------------------------
NAME       : Send Data(untigned char)
DESCRIPE    : send data, simulate SPI to send data for controling the ad9954;
-----------------------------------------------------------------*/
void SendData (unst16 data)

{  	unst16 i=0;
  //  AD9954_DDSSYN_OFF;
	for(i=0;i<8;i++){ 
		AD9954_DDSCLK_OFF;	
  if((data&0x80)!=0){
   		AD9954_DDSSDI_ON;
        }
	else {
	 AD9954_DDSSDI_OFF;
				}	   

		AD9954_DDSCLK_ON;		
	data<<=1; 
	  	}
 // AD9954_DDSSYN_ON;
}