void OneWireSearchRom(void) {
unsigned char bit,bit_complementary,pozycja,buffer[NUM_OF_THERMS];
for(unsigned char i=0;i < NUM_OF_THERMS;i++) {
buffer[i]=0;
}
for(unsigned char i=0;i < NUM_OF_THERMS;i++) {
pozycja=0;
if (!OneWireReset()) return;
OneWireWriteByte(0xF0);
for(unsigned char bitNo=0;bitNo<64;bitNo++) {
bit=OneWireReadBit();
bit_complementary=OneWireReadBit();
if ((!(bit|bit_complementary))&1) {
if(buffer[pozycja+1]==0) {
buffer[pozycja]++;
}
OneWireWriteBit((buffer[pozycja]-1));
ROM[i][bitNo/8]|=((buffer[pozycja]-1))<<(bitNo%8);
pozycja++;
}
else {
OneWireWriteBit(bit);
ROM[i][bitNo/8]|=bit<<(bitNo%8);
}
}
while(buffer[pozycja-1]==2) {
buffer[pozycja]=0;
pozycja--;
}
}
}
u8 DS18B20GetNext(u8 pin)
{
u8 m = 1; // ROM Bit index
u8 n = 0; // ROM Byte index
u8 k = 1; // bit mask
u8 x = 0;
u8 discrepMarker = 0; // discrepancy marker
u8 g; // Output bit
u8 nxt; // return value
int flag;
nxt = FALSE; // set the next flag to false
dowcrc = 0; // reset the dowcrc
flag = OneWireReset(pin); // reset the 1-wire
if(flag||doneFlag) // no parts -> return false
{
lastDiscrep = 0; // reset the search
return FALSE;
}
// send SearchROM command for all eight bytes
OneWireWrite(pin, SEARCHROM);
do {
x = 0;
if(OneWireReadBit(pin) == 1) x = 2;
//myDelay_10us(12);
if(OneWireReadBit(pin) == 1 ) x |= 1;
if(x == 3)
break;
else
{
if(x > 0) // all devices coupled have 0 or 1
g = x >> 1; // bit write value for search
else
{
// if this discrepancy is before the last
// discrepancy on a previous Next then pick
// the same as last time
if(m < lastDiscrep)
g = ( (ROM[n] & k) > 0);
else // if equal to last pick 1
g = (m == lastDiscrep); // if not then pick 0
// if 0 was picked then record position with mask k
if (g == 0) discrepMarker = m;
}
if (g == 1) // isolate bit in ROM[n] with mask k
ROM[n] |= k;
else
ROM[n] &= ~k;
OneWireWriteBit(pin, g); // ROM search write
m++; // increment bit counter m
k = k << 1; // and shift the bit mask k
if(k == 0) // if the mask is 0 then go to new ROM
{ // byte n and reset mask
DS18B20_crc(ROM[n]); // accumulate the CRC
n++;
k++;
}
}
} while (n < 8); // loop until through all ROM bytes 0-7
if(m < 65 || dowcrc) // if search was unsuccessful then
lastDiscrep=0; // reset the last discrepancy to 0
else // search was successful, so set lastDiscrep, lastOne, nxt
{
lastDiscrep = discrepMarker;
doneFlag = (lastDiscrep == 0);
nxt = TRUE; // indicates search is not complete yet, more parts remain
}
return nxt;
}
