Commit c14adfdf authored by Erik Strand's avatar Erik Strand

Try to use OneWire (but not enough memory)

parent c9aca3f7
......@@ -115,6 +115,8 @@ void put_string(volatile unsigned char *port, unsigned char pin, char *str) {
} while (str[index] != 0);
}
OneWire ds(11); // on pin 10 (a 4.7K resistor is necessary)
void setup(void) {
// Set clock divider to 1.
CLKPR = (1 << CLKPCE);
......@@ -134,15 +136,112 @@ void setup(void) {
PORTA |= button_pin;
}
void loop() {
// Turn on the LED when the button is pressed.
void loop(void) {
if (PINA & button_pin) {
// Turn off the LED.
PORTB &= ~led_pin;
put_char(&serial_port, serial_pin_out, '0');
//put_char(&serial_port, serial_pin_out, '0');
} else {
PORTB |= led_pin;
put_char(&serial_port, serial_pin_out, '1');
//put_char(&serial_port, serial_pin_out, '1');
}
byte i;
byte present = 0;
byte type_s;
byte data[12];
byte addr[8];
float celsius, fahrenheit;
if ( !ds.search(addr)) {
put_string(&serial_port, serial_pin_out, "No more addresses.");
ds.reset_search();
delay(250);
return;
}
//Serial.print("ROM =");
put_string(&serial_port, serial_pin_out, "ROM=");
for( i = 0; i < 8; i++) {
put_char(&serial_port, serial_pin_out, ' ');
//Serial.print(addr[i], HEX);
put_string(&serial_port, serial_pin_out, "xxx");
//put_string(&serial_port, serial_pin_out, addr[i])
}
if (OneWire::crc8(addr, 7) != addr[7]) {
put_string(&serial_port, serial_pin_out, "CRC is not valid!");
return;
}
//Serial.println();
// the first ROM byte indicates which chip
switch (addr[0]) {
case 0x10:
put_string(&serial_port, serial_pin_out, " Chip = DS18S20"); // or old DS1820
type_s = 1;
break;
case 0x28:
put_string(&serial_port, serial_pin_out, " Chip = DS18B20");
type_s = 0;
break;
case 0x22:
put_string(&serial_port, serial_pin_out, " Chip = DS1822");
type_s = 0;
break;
default:
put_string(&serial_port, serial_pin_out, "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
put_string(&serial_port, serial_pin_out, " Data = ");
put_string(&serial_port, serial_pin_out, "xxx");
//put_string(&serial_port, serial_pin_out, present, HEX);
put_string(&serial_port, serial_pin_out, " ");
for ( i = 0; i < 9; i++) { // we need 9 bytes
data[i] = ds.read();
//Serial.print(data[i], HEX);
put_string(&serial_port, serial_pin_out, " thing");
}
put_string(&serial_port, serial_pin_out, " CRC=");
//put_string(&serial_port, serial_pin_out, OneWire::crc8(data, 8), HEX);
// 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
}
_delay_us(10000);
celsius = (float)raw / 16.0;
fahrenheit = celsius * 1.8 + 32.0;
put_string(&serial_port, serial_pin_out, " Temperature = ");
//put_string(&serial_port, serial_pin_out, celsius);
put_string(&serial_port, serial_pin_out, " Celsius, ");
//put_string(&serial_port, serial_pin_out, fahrenheit);
put_string(&serial_port, serial_pin_out, " Fahrenheit");
}
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