From fe742e35d3fa6d69125e9f463cbbe1c6032969ca Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@windfisch.org>
Date: Sun, 29 Nov 2015 18:15:21 +0100
Subject: meeh

---
 avr/1wire.c | 239 ++++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 151 insertions(+), 88 deletions(-)

(limited to 'avr/1wire.c')

diff --git a/avr/1wire.c b/avr/1wire.c
index 237abb9..5dbca82 100644
--- a/avr/1wire.c
+++ b/avr/1wire.c
@@ -9,122 +9,185 @@
 #include <util/delay.h>
 #include <avr/io.h>
 #include <avr/interrupt.h>
+#include "1wire.h"
 
 #ifndef W1_PIN
-#define W1_PIN	PA0
-#define W1_IN	PINA
-#define W1_OUT	PORTA
-#define W1_DDR	DDRA
+#define W1_PIN	PB4
+#define W1_IN	PINB
+#define W1_OUT	PORTB
+#define W1_DDR	DDRB
 #endif
 
 uint8_t buff[2];
 
+
+#define hard_gnd do { W1_OUT &= ~(1<<W1_PIN); W1_DDR |= 1<<W1_PIN; } while(0)
+#define hard_vcc do { W1_OUT |= 1<<W1_PIN; W1_DDR |= 1<<W1_PIN; } while(0)
+#define soft_vcc do { W1_DDR &= ~(1<<W1_PIN); W1_OUT |= 1<<W1_PIN; } while(0)
+#define tristate do { W1_DDR &= ~(1<<W1_PIN); W1_OUT &= ~(1<<W1_PIN); } while(0)
+
+/*uint8_t w1_reset(void)
+{
+	uint8_t err = 0;
+
+	hard_gnd;
+
+	_delay_us(480 );			// 480 us
+	cli();
+	
+	soft_vcc;
+	
+	_delay_us( 66 );
+	if (W1_IN & (1<<W1_PIN))			// no presence detect
+		err = 1;
+	sei();
+	_delay_us( 480 - 66 );
+	if( (W1_IN & (1<<W1_PIN)) == 0 )		// short circuit
+		err = 2;
+	return err;
+}*/
+
 uint8_t w1_reset(void)
 {
-  uint8_t err;
-
-  W1_OUT &= ~(1<<W1_PIN);
-  W1_DDR |= 1<<W1_PIN;
-  _delay_us(480 );			// 480 us
-  cli();
-  W1_DDR &= ~(1<<W1_PIN);
-  _delay_us( 66 );
-  err = W1_IN & (1<<W1_PIN);			// no presence detect
-  sei();
-  _delay_us( 480 - 66 );
-  if( (W1_IN & (1<<W1_PIN)) == 0 )		// short circuit
-    err = 1;
-  return err;
+	uint8_t err = 0;
+
+	hard_gnd;
+
+	_delay_us(480 );			// 480 us
+	cli();
+	
+	hard_vcc;
+	_delay_us(33);
+	soft_vcc;
+	
+	_delay_us( 66-33 );
+	if (W1_IN & (1<<W1_PIN))			// no presence detect
+		err = 1;
+	sei();
+	_delay_us( 480 - 66 );
+	if( (W1_IN & (1<<W1_PIN)) == 0 )		// short circuit
+		err = 2;
+	return err;
 }
 
 
 uint8_t w1_bit_io( uint8_t b )
 {
-  cli();
-  W1_DDR |= 1<<W1_PIN;
-  _delay_us( 1 );
-  if( b )
-    W1_DDR &= ~(1<<W1_PIN);
- _delay_us( 15 - 1 );
-  if( (W1_IN & (1<<W1_PIN)) == 0 )
-    b = 0;
-  _delay_us( 60 - 15 );
-  W1_DDR &= ~(1<<W1_PIN);
-  sei();
-  return b;
+	cli();
+	hard_gnd;
+
+	_delay_us( 1 );
+	if( b )
+	{
+		//hard_vcc;
+		//asm volatile("nop" ::: );
+		soft_vcc;
+	}
+	_delay_us( 15 - 1 );
+	if( (W1_IN & (1<<W1_PIN)) == 0 )
+		b = 0;
+	_delay_us( 60 - 15 );
+	soft_vcc;
+	sei();
+	return b;
 }
 
 
-uint w1_byte_wr( uint8_t b )
+uint8_t w1_byte_wr( uint8_t b )
 {
-  uint8_t i = 8, j;
-  do{
-    j = w1_bit_io( b & 1 );
-    b >>= 1;
-    if( j )
-      b |= 0x80;
-  }while( --i );
-  return b;
+	uint8_t i = 8, j;
+	do
+	{
+		j = w1_bit_io( b & 1 );
+		b >>= 1;
+		if( j )
+			b |= 0x80;
+	}
+	while( --i );
+	return b;
 }
 
 
-uint w1_byte_rd( void )
+uint8_t w1_byte_rd( void )
 {
-  return w1_byte_wr( 0xFF );
+	return w1_byte_wr( 0xFF );
 }
 
 
-uint8_t w1_rom_search( uint8_t diff, uint8_t idata *id )
+uint8_t w1_rom_search( uint8_t diff, uint8_t *id )
 {
-  uint8_t i, j, next_diff;
-  uint8_t b;
-
-  if( w1_reset() )
-    return PRESENCE_ERR;			// error, no device found
-  w1_byte_wr( SEARCH_ROM );			// ROM search command
-  next_diff = LAST_DEVICE;			// unchanged on last device
-  i = 8 * 8;					// 8 bytes
-  do{
-    j = 8;					// 8 bits
-    do{
-      b = w1_bit_io( 1 );			// read bit
-      if( w1_bit_io( 1 ) ){			// read complement bit
-	if( b )					// 11
-	  return DATA_ERR;			// data error
-      }else{
-	if( !b ){				// 00 = 2 devices
-	  if( diff > i ||
-	    ((*id & 1) && diff != i) ){
-	    b = 1;				// now 1
-	    next_diff = i;			// next pass 0
-	  }
+	uint8_t i, j, next_diff;
+	uint8_t b;
+
+	if( w1_reset() )
+		return PRESENCE_ERR;			// error, no device found
+	w1_byte_wr( SEARCH_ROM );			// ROM search command
+	next_diff = LAST_DEVICE;			// unchanged on last device
+	i = 8 * 8;					// 8 bytes
+	do
+	{
+		j = 8;					// 8 bits
+		do
+		{
+			b = w1_bit_io( 1 );			// read bit
+			if( w1_bit_io( 1 ) ) 			// read complement bit
+			{
+				if( b )					// 11
+					return DATA_ERR;			// data error
+			}
+			else
+			{
+				if( !b ) 				// 00 = 2 devices
+				{
+					if( diff > i ||
+					        ((*id & 1) && diff != i) )
+					{
+						b = 1;				// now 1
+						next_diff = i;			// next pass 0
+					}
+				}
+			}
+			w1_bit_io( b );     			// write bit
+			*id >>= 1;
+			if( b )					// store bit
+				*id |= 0x80;
+			i--;
+		}
+		while( --j );
+		id++;					// next byte
 	}
-      }
-      w1_bit_io( b );     			// write bit
-      *id >>= 1;
-      if( b )					// store bit
-	*id |= 0x80;
-      i--;
-    }while( --j );
-    id++;					// next byte
-  }while( i );
-  return next_diff;				// to continue search
+	while( i );
+	return next_diff;				// to continue search
 }
 
+void ds1992_read(uint16_t addr, uint8_t* buf, uint8_t len)
+{
+	w1_byte_wr(SKIP_ROM);
+	w1_byte_wr(0xF0); // read
+	w1_byte_wr((addr & 0x00FF));
+	w1_byte_wr((addr & 0xFF00) >> 8);
+	for (int i=0; i < len; i++)
+		buf[i] = w1_byte_rd();
+}
 
-void w1_command( uint8_t command, uint8_t idata *id )
+void w1_command( uint8_t command, uint8_t *id )
 {
-  uint8_t i;
-  w1_reset();
-  if( id ){
-    w1_byte_wr( MATCH_ROM );			// to a single device
-    i = 8;
-    do{
-      w1_byte_wr( *id );
-      id++;
-    }while( --i );
-  }else{
-    w1_byte_wr( SKIP_ROM );			// to all devices
-  }
-  w1_byte_wr( command );
+	uint8_t i;
+	w1_reset();
+	if( id )
+	{
+		w1_byte_wr( MATCH_ROM );			// to a single device
+		i = 8;
+		do
+		{
+			w1_byte_wr( *id );
+			id++;
+		}
+		while( --i );
+	}
+	else
+	{
+		w1_byte_wr( SKIP_ROM );			// to all devices
+	}
+	w1_byte_wr( command );
 }
-- 
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