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;
}
uint w1_byte_wr( uchar b )
{
uchar i = 8, j;
do {
j = w1_bit_io( b & 1 );
b >>= 1;
if( j )
b |= 0x80;
} while( --i );
return b;
}
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
}
}
}
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
}
