上面的18B20的溫度變化只有0.5,應該怎么修改以下，能讓溫度在0.01就變化
- #include <OneWire.h>
- OneWire ds(10); // on pin 10 (a 4.7K resistor is necessary)
- void setup(void) {
- Serial.begin(9600);
- }
- void loop(void) {
- byte i;
- byte present = 0;
- byte type_s;
- byte data[9];
- byte addr[8];
- float celsius, fahrenheit;
-
- if ( !ds.search(addr)) {
- Serial.println("No more addresses.");
- Serial.println();
- ds.reset_search();
- delay(250);
- return;
- }
-
- Serial.print("ROM =");
- for( i = 0; i < 8; i++) {
- Serial.write(' ');
- Serial.print(addr[i], HEX);
- }
- if (OneWire::crc8(addr, 7) != addr[7]) {
- Serial.println("CRC is not valid!");
- return;
- }
- Serial.println();
-
- // the first ROM byte indicates which chip
- switch (addr[0]) {
- case 0x10:
- Serial.println(" Chip = DS18S20"); // or old DS1820
- type_s = 1;
- break;
- case 0x28:
- Serial.println(" Chip = DS18B20");
- type_s = 0;
- break;
- case 0x22:
- Serial.println(" Chip = DS1822");
- type_s = 0;
- break;
- default:
- Serial.println("Device is not a DS18x20 family device.");
- return;
- }
- ds.reset();
- ds.select(addr);
- ds.write(0x44, 1); // start conversion, with parasite power on at the end
-
- delay(1000); // maybe 750ms is enough, maybe not
- // we might do a ds.depower() here, but the reset will take care of it.
-
- present = ds.reset();
- ds.select(addr);
- ds.write(0xBE); // Read Scratchpad
- Serial.print(" Data = ");
- Serial.print(present, HEX);
- Serial.print(" ");
- for ( i = 0; i < 9; i++) { // we need 9 bytes
- data[i] = ds.read();
- Serial.print(data[i], HEX);
- Serial.print(" ");
- }
- Serial.print(" CRC=");
- Serial.print(OneWire::crc8(data, 8), HEX);
- Serial.println();
- // Convert the data to actual temperature
- // because the result is a 16 bit signed integer, it should
- // be stored to an "int16_t" type, which is always 16 bits
- // even when compiled on a 32 bit processor.
- int16_t raw = (data[1] << 8) | data[0];
- if (type_s) {
- raw = raw << 3; // 9 bit resolution default
- if (data[7] == 0x10) {
- // "count remain" gives full 12 bit resolution
- raw = (raw & 0xFFF0) + 12 - data[6];
- }
- } else {
- byte cfg = (data[4] & 0x60);
- // at lower res, the low bits are undefined, so let's zero them
- if (cfg == 0x00) raw = raw & ~7; // 9 bit resolution, 93.75 ms
- else if (cfg == 0x20) raw = raw & ~3; // 10 bit res, 187.5 ms
- else if (cfg == 0x40) raw = raw & ~1; // 11 bit res, 375 ms
- //// default is 12 bit resolution, 750 ms conversion time
- }
- celsius = (float)raw / 16.0;
- fahrenheit = celsius * 1.8 + 32.0;
- Serial.print(" Temperature = ");
- Serial.print(celsius);
- Serial.print(" Celsius, ");
- Serial.print(fahrenheit);
- Serial.println(" Fahrenheit");
- }
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