Looked through the help file in mikroC and found som code on how to use the DS1820 temp sensor (look further down for the code. But I cant get it to work. I have put in the temp sensor the round side on the temp senor is on the round side marking on the board. All three legs are in. And the jumper is set to RA5. But all that displays on the LCD is:
Temperature:
0.0000 CCC
Maybe there is something worng with the code or me new sensor (got it with the board two days ago) is broken. Can someone suggest a solution?
//Andi
P.S. easyPic 2 is one of the greates test boards I have used!!! D.S
Code: Select all
// Set TEMP_RESOLUTION to the corresponding resolution of your DS18x20 sensor:
// 18S20: 9
// 18B20: 12 (default setting; can be 9,10,11,or 12)
const unsigned short TEMP_RESOLUTION = 12;
const int RES_FACTOR_1[4] = {5000, 2500, 1250, 625};
const unsigned int RES_FACTOR_2[4] = {0x0001, 0x0003, 0x0007, 0x000F};
const unsigned int RES_FACTOR_3[4] = {0x8000, 0xC000, 0xE000, 0xF000};
unsigned temp;
unsigned short j, RES_SHIFT;
void Display_Temperature(unsigned int temp) {
const unsigned short RES_SHIFT = TEMP_RESOLUTION - 8;
unsigned int temp_whole, temp_fraction;
unsigned short i;
char text[8];
// Isolate the fraction and make it a 4-digit decimal integer (for display)
temp_fraction = temp & RES_FACTOR_2[RES_SHIFT - 1];
temp_fraction = temp_fraction * RES_FACTOR_1[RES_SHIFT - 1];
//portc = temp_fraction;
// Handle the whole part of temperature value
temp_whole = temp;
// Is temperature negative?
if ((temp_whole & 0x8000) != 0u) i = 1; // Yes, i = 1
else i = 0; // No, i = 0
PORTC = i;
// Remove the fractional part
temp_whole >>= RES_SHIFT;
// Correct the sign if necessary
if (i) temp_whole |= RES_FACTOR_3[RES_SHIFT - 1];
//portd = temp_whole;
IntToStr(temp_whole, text); // Convert whole part to string
LCD_Out(2, 6, text); // Print whole part on LCD
LCD_Chr_CP('.'); // Print dot to separate fractional part
IntToStr(temp_fraction, text); // Convert fractional part to string
// Add leading zeroes (we display 4 digits fractional part)
if (temp_fraction < 1000u) LCD_Chr_CP('0');
if (temp_fraction < 100u) LCD_Chr_CP('0');
if (temp_fraction < 10u) LCD_Chr_CP('0');
LCD_Out_CP(text); // Print fractional part on LCD
LCD_Chr_CP(223); // Print degree character
LCD_Chr_CP('C'); // Print 'C' for Centigrades
}//~
void main() {
ADCON1 = 0xFF; // Configure RA5 pin as digital I/O
PORTE = 0xFF;
TRISE = 0x0F; // PORTE is input
PORTB = 0;
TRISB = 0; // PORTB is output
// Initialize LCD on PORTB and prepare for output
LCD_Init(&PORTB);
LCD_Cmd(LCD_CURSOR_OFF);
LCD_Out(1, 1, " Temperature: ");
do { // main loop
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
Delay_ms(400);
j = OW_Read(&PORTE,2); // Get temperature LSB
temp = OW_Read(&PORTE,2); // Get temperature MSB
temp <<= 8; temp += j; // Form the result
Display_Temperature(temp); // Format and display result on LCD
Delay_ms(500);
} while (1);
}//~!
