// Set TEMP_RESOLUTION to the corresponding resolution of used DS18x20 sensor:
// 18S20: 9 (default setting; can be 9,10,11,or 12)
// 18B20: 12
const unsigned short TEMP_RESOLUTION = 12;
char *text = "000.0000";
unsigned temp;
void Display_Temperature(unsigned int temp2write) {
const unsigned short RES_SHIFT = TEMP_RESOLUTION - 8;
char temp_whole;
unsigned int temp_fraction;
// check if temperature is negative
if (temp2write & 0x8000) {
text[0] = '-';
temp2write = ~temp2write + 1;
}
// extract temp_whole
temp_whole = temp2write >> RES_SHIFT ;
// convert temp_whole to characters
if (temp_whole/100)
text[0] = temp_whole/100 + 48;
text[1] = (temp_whole/10)%10 + 48; // extract tens digit
text[2] = temp_whole%10 + 48; // extract ones digit
// extract temp_fraction and convert it to unsigned int
temp_fraction = temp2write << (4-RES_SHIFT);
temp_fraction &= 0x000F;
temp_fraction *= 625;
// convert temp_fraction to characters
text[4] = temp_fraction/1000 + 48; // extract thousands digit
text[5] = (temp_fraction/100)%10 + 48; // extract hundreds digit
text[6] = (temp_fraction/10)%10 + 48; // extract tens digit
text[7] = temp_fraction%10 + 48; // extract ones digit
// print temperature on LCD
Lcd_Out(2, 5, text);
}//~
void main() {
ADCON1 = 7; // Configure AN pins as digital I/O
Lcd_Init(&PORTD); // Lcd_Init_EP4, see Autocomplete
Lcd_Cmd(LCD_CURSOR_OFF);
Lcd_Out(1, 1, " Temperature: ");
// Print degree character, 'C' for Centigrades
Lcd_Chr(2,13,223);
Lcd_Chr(2,14,'C');
//--- main loop
do {
//--- perform temperature reading
Ow_Reset(&PORTE,2); // Onewire reset signal
Ow_Write(&PORTE,2,0xCC); // Issue command SKIP_ROM
Ow_Write(&PORTE,2,0x44); // Issue command CONVERT_T
Delay_us(120);
Ow_Reset(&PORTE,2);
Ow_Write(&PORTE,2,0xCC); // Issue command SKIP_ROM
Ow_Write(&PORTE,2,0xBE); // Issue command READ_SCRATCHPAD
temp = Ow_Read(&PORTE,2);
temp = (Ow_Read(&PORTE,2) << 8) + temp;
//--- Format and display result on Lcd
Display_Temperature(temp);
Delay_ms(500);
} while (1);
}