/* 
 * Title       : ds1822.c
 * Description : DS1822 subroutine
 * Author      : KAWAMOTO Yasuhisa
 * URL         : http://www.devdrv.co.jp/
 * Date        : 01/13/2006
 */
 
//-----------------------------------------------------------------------------
// Includes
//-----------------------------------------------------------------------------
#include <c8051f330.h>
#include "main.h"

//-----------------------------------------------------------------------------
// init_ds1822
//-----------------------------------------------------------------------------
void init_ds1822(void)
{
	unsigned char i;
	
	// Read Scratchpad
	OWTouchReset();
	OWWriteByte(0x55);
	for(i = 0; i < 8; i++)
		OWWriteByte(ROMCode[i]);
	OWWriteByte(0xBE);
	for(i = 0; i < 9; i++)
	{
		ScratchPAD[i] = OWReadByte();
	}
#ifdef DEBUG
		uart0_put_val(ScratchPAD[4]);
#endif
	
		if((ScratchPAD[4] & 0x60) != 0x60)
	{
		// Write Scratchpad
		OWTouchReset();
		OWWriteByte(0x55);
		for(i = 0; i < 8; i++)
			OWWriteByte(ROMCode[i]);
		OWWriteByte(0x4E);
		OWWriteByte(0x00);
		OWWriteByte(0x00);
		OWWriteByte(ScratchPAD[4] | 0x60);		// R1,R0 = 11b(12bit)
	}
#ifdef DEBUG
	uart0_put_char('\r');
	uart0_put_char('\n');
#endif
}

//-----------------------------------------------------------------------------
// ds1822
//-----------------------------------------------------------------------------
void ds1822(void)
{
	unsigned char i;
	
	for(i = 0; i < 8; i++)
		uart0_put_val(ROMCode[i]);
	
	// Convert T
	OWTouchReset();
	OWWriteByte(0x55);
	for(i = 0; i < 8; i++)
		OWWriteByte(ROMCode[i]);
	OWWriteByte(0x44);
	
	for(i = 0; i < 75; i++)						//  tCONV = 750ms(12bit)
		tickDelay(10000*(SYSCLK/100000)/140);
	
	// Read Scratchpad
	OWTouchReset();
	OWWriteByte(0x55);
	for(i = 0; i < 8; i++)
		OWWriteByte(ROMCode[i]);
	OWWriteByte(0xBE);
	for(i = 0; i < 9; i++)
	{
		uart0_put_val(OWReadByte());
	}
	
	uart0_put_char('\r');
	uart0_put_char('\n');
}