adc_drv.c

TDA7540 收音机程序

/***************************************************************************
Project  :   TDA7540 Jig board 
Compiler : ST7 HiCross C (HiWARE)
Module   :  Adc_drv.c
Version  :  V 1.0
Created  : Jan.24th,2005 
Author   :  Jerry HE / ST-ShenZhen
Description
         -  Analog converter handle program
Modified
	  -    
***************************************************************************/


/* EXTERNAL DECLARATIONS *****************************************************/
/* List of all the variables defined in another module and used in this one. */
/* MODEL => #include [file_name].h                                           */

#include "system.h"

/* STATIC DECLARATIONS *******************************************************/
/* List of all the variables/constant defined in another module and used in  */
/* this one.                                                                 */
/* MODEL => static type_name var_name;  or #define                           */
/*+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Routine : Read_ADKey
Input   : 
Output  : 
Description 
        - Analog key convertion
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
void Read_ADKey()
{
	if (ADKeyDelay!=0)
	return;
	if(!BitVal(ADC_COCO))
	return;
	if(F_ADKeyRead ==1)
	return;
	switch(ADStatus)
	{
	//The first line of switch
	   case  AD_Key1:
	   	ADKey[0]=ADC_DR;
		ADStatus=AD_Key2;
		ADC_CR =(ADC_START|ADStatus);
	   	break;
	   case  AD_Key2:
	       ADKey[1]=ADC_DR;
		ADStatus=AD_Key1;
		ADC_CR =(ADC_START|ADStatus);
		F_ADKeyRead = 1;
	   	break;
	   default:
	   	ADStatus=AD_Key1;
		ADC_CR =(ADC_START|ADStatus);
	   	break;
	}
	ADKeyDelay = 4;
}

/*+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Routine : Init_AD
Input   : 
Output  : 
Description 
        - Initial ST7 AD converter
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
void Init_AD()
{
    ADStatus= AD_Key1;
    ADC_CR=(ADC_START|ADStatus);
}

/*+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Routine : ADC_GetValue
Input   : Channel No to be read [0..7]
Output  : ADC_DR
Description 
        - A/D Conversion on the selected Channel.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ 
unsigned char ADC_GetValue (unsigned char adc_channel)
{
	ADC_CR= ((adc_channel & 0x0F) | 0x20);
	while ((ADC_CR&0x80)==0);        /* Wait for End of Conversion */
	return(ADC_DR);                     /* Return the value */
}


/*** (c) 2005  STMicroelectronics ************************************* END OF FILE ***/