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--;
}
}
}
int ds18b20_Read(){
for(int i=0;i < NUM_OF_THERMS;i++){
unsigned char scratchpad[2];
if (!OneWireReset()) {return 0;}
if(NUM_OF_THERMS > 1){
OneWireWriteByte(0x55);
for(int j=0;j<8;j++){
OneWireWriteByte(ROM[i][j]);
}
} else{
OneWireWriteByte(0xcc);
}
OneWireWriteByte(0xBE);
for(int k=0; k<2; k++) scratchpad[k] = OneWireReadByte();
temperatures[i]= ((scratchpad[1] << 8) + scratchpad[0]) / 16.0;
}
return 1;
}
int ds18b20_SetResolution(char resolution)
{
if(resolution == 12){
resolution = 0x7F;
}
else if(resolution == 11){
resolution = 0x5F;
}
else if(resolution == 10){
resolution = 0x3F;
}
else if(resolution == 9){
resolution = 0x1F;
}
else{
resolution = 0x7F;
}
for(int i=0;i < NUM_OF_THERMS;i++){
if (!OneWireReset()) {return 0;}
if(NUM_OF_THERMS > 1){
OneWireWriteByte(0x55);
for(int j=0;j<8;j++){
OneWireWriteByte(ROM[i][j]);
}
} else{
OneWireWriteByte(0xcc);
}
OneWireWriteByte(0x4E);
OneWireWriteByte(0x00);
OneWireWriteByte(0x00);
OneWireWriteByte(resolution);
if (!OneWireReset()) {return 0;}
OneWireWriteByte(0x55);
for(int j=0;j<8;j++){
OneWireWriteByte(ROM[i][j]);
}
OneWireWriteByte(0x48);
_delay_ms(10);
}
return 1;
}
unsigned char OneWireTouchByte(unsigned char sendbyte)
{
if (sendbyte == 0xff)
return OneWireReadByte();
else
{
OneWireWriteByte(sendbyte);
return sendbyte;
}
}
unsigned char ds18b20_ConvertT(void){
if (!OneWireReset()) return 0;
OneWireWriteByte(0xcc); // SKIP ROM
OneWireWriteByte(0x44); // CONVERT T
return -1;
}
/**
* The 'OneWireSearch' function does a general search. This function continues from
* the previous search state. The search state can be reset by using the
* 'OneWireFirst' function.
*
* @retval true When a 1-Wire device was found and its Serial Number placed in
* the global ROM
* @retval false When no new device was found. Either the last search was
* the last device or there are no devices on the 1-Wire Net.
*/
unsigned char OneWireSearch(void)
{
unsigned char id_bit_number;
unsigned char last_zero, rom_byte_number, search_result;
unsigned char id_bit, cmp_id_bit;
unsigned char rom_byte_mask, search_direction, status;
// initialize for search
id_bit_number = 1;
last_zero = 0;
rom_byte_number = 0;
rom_byte_mask = 1;
search_result = false;
// if the last call was not the last one
if (!LastDeviceFlag)
{
// 1-Wire reset
if (!OneWireReset())
{
// reset the search
LastDiscrepancy = 0;
LastDeviceFlag = false;
LastFamilyDiscrepancy = 0;
return false;
}
// issue the search command
OneWireWriteByte(0xF0);
// loop to do the search
do
{
// if this discrepancy if before the Last Discrepancy
// on a previous next then pick the same as last time
if (id_bit_number < LastDiscrepancy)
{
if ((ROM_NO[rom_byte_number] & rom_byte_mask) > 0)
search_direction = 1;
else
search_direction = 0;
}
else
{
// if equal to last pick 1, if not then pick 0
if (id_bit_number == LastDiscrepancy)
search_direction = 1;
else
search_direction = 0;
}
// Perform a triple operation on the DS2482 which will perform
// 2 read bits and 1 write bit
status = DS2482SearchTriplet(search_direction);
// check bit results in status byte
id_bit = ((status & DS2482_STATUS_SBR) == DS2482_STATUS_SBR);
cmp_id_bit = ((status & DS2482_STATUS_TSB) == DS2482_STATUS_TSB);
search_direction =
((status & DS2482_STATUS_DIR) == DS2482_STATUS_DIR) ? (unsigned char) 1 : (unsigned char) 0;
// check for no devices on 1-Wire
if ((id_bit) && (cmp_id_bit))
break;
else
{
if ((!id_bit) && (!cmp_id_bit) && (search_direction == 0))
{
last_zero = id_bit_number;
// check for Last discrepancy in family
if (last_zero < 9)
LastFamilyDiscrepancy = last_zero;
}
// set or clear the bit in the ROM byte rom_byte_number
// with mask rom_byte_mask
if (search_direction == 1)
ROM_NO[rom_byte_number] |= rom_byte_mask;
else
ROM_NO[rom_byte_number] &= (unsigned char) ~rom_byte_mask;
// increment the byte counter id_bit_number
// and shift the mask rom_byte_mask
id_bit_number++;
rom_byte_mask <<= 1;
// if the mask is 0 then go to new SerialNum byte rom_byte_number
// and reset mask
if (rom_byte_mask == 0)
{
rom_byte_number++;
rom_byte_mask = 1;
}
}
}
while (rom_byte_number < 8); // loop until through all ROM bytes 0-7
// if the search was successful then
if (!(id_bit_number < 65))
{
// search successful so set LastDiscrepancy,LastDeviceFlag
// search_result
LastDiscrepancy = last_zero;
// check for last device
if (LastDiscrepancy == 0)
LastDeviceFlag = true;
search_result = true;
}
}
// if no device found then reset counters so next
// 'search' will be like a first
if (!search_result || (ROM_NO[0] == 0))
{
LastDiscrepancy = 0;
LastDeviceFlag = false;
LastFamilyDiscrepancy = 0;
search_result = false;
}
return search_result;
}