ad.c

nec 78K0 样例对程序初始化电表样

/*
*******************************************************************************
**
**  This device driver was created by Applilet for the 78K0/KB2, 78K0/KC2,
**  78K0/KD2, 78K0/KE2 and 78K0/KF2 8-Bit Single-Chip Microcontrollers.
**
**  Copyright(C) NEC Electronics Corporation 2002 - 2005
**  All rights reserved by NEC Electronics Corporation.
**
**  This program should be used on your own responsibility.
**  NEC Electronics Corporation assumes no responsibility for any losses
**  incurred by customers or third parties arising from the use of this file.
**
**  Filename :	ad.c
**  Abstract :	This file implements device driver for AD module.
**  APIlib :	NEC78K0KX2.lib V1.01 [09 Aug. 2005]
**
**  Device :	uPD78F0513(44-pin)
**
**  Compiler :	NEC/CC78K0
**
*******************************************************************************
*/
/*
*******************************************************************************
**  Include files
*******************************************************************************
*/
#include "macrodriver.h"
#include "ad.h"

/*
**-----------------------------------------------------------------------------
**
**  Abstract:
**	This function initializes A/D module.
**
**  Parameters:
**	None
**
**  Returns:
**	None
**
**-----------------------------------------------------------------------------
*/
void AD_Init( void )
{
	ADPC = AD_ADPC;
	ADS = AD_ADS;
	ClrIORBit(ADM, 0x02);			/* 2.7V<=AVref<=5.5V */
	ADM = ADM & AD_ADM;
}

/*
**-----------------------------------------------------------------------------
**
**  Abstract:
**	This function starts the A/D converter.
**
**  Parameters:
**	None
**
**  Returns:
**	MD_OK
**
**-----------------------------------------------------------------------------
*/
MD_STATUS AD_Start( void )
{
	int delay = 200;
	SetIORBit(ADM, 0x01);			/* comparator operation */
	while(delay--);
	
	SetIORBit(ADM, 0x80);
	return MD_OK;
}

/*
**-----------------------------------------------------------------------------
**
**  Abstract:
**	This function can be called after an A/D conversion is completed,
**	and returns the conversion result(s) in the buffer.
**
**  Parameters:
**	buffer	The address where to write the conversion result.
**
**  Returns:
**	MD_OK
**
**-----------------------------------------------------------------------------
*/
MD_STATUS AD_Read( USHORT* buffer )
{
	*buffer = (USHORT)( ADCR >> 6 );
	return MD_OK;
}

/*
**-----------------------------------------------------------------------------
**
**  Abstract:
**	This function stops the A/D converter.
**
**  Parameters:
**	None
**
**  Returns:
**	MD_OK
**
**-----------------------------------------------------------------------------
*/
MD_STATUS AD_Stop( void )
{
	
	ClrIORBit(ADM, 0x81);
	return MD_OK;
}