Electric Dollar Store

The LM75B is a temperature-to-digital converter with an I²C interface. The temperature register is an 11-bit signed quantity, giving a resolution of 0.125 °C. 

import sys
import time

from i2cdriver import I2CDriver, EDS

if __name__ == '__main__':
    i2 = I2CDriver(sys.argv[1])

    d = EDS.Temp(i2)
    for i in range(20):
        celsius = d.read()
        fahrenheit = celsius * 9/5 + 32
        sys.stdout.write("%.1f C  %.1f F\n" % (celsius, fahrenheit))
        time.sleep(.1)

#include <Wire.h>

float temp_read()
{
  Wire.requestFrom(0x48, 2);
  byte h = Wire.read();
  byte l = Wire.read();
  return ((h << 3) | (l >> 5)) * 0.125;
}

void setup() {
  Serial.begin(115200);
  Wire.begin();
}

void loop() {
  Serial.println(temp_read());
  delay(20);
}

from machine import I2C
import struct
import time

class Temp:
    """ TEMP is an LM75B temperature sensor """
    def __init__(self, i2, a = 0x48):
        self.i2 = i2
        self.a = a

    def regrd(self, r):
        return struct.unpack(">h", self.i2.readfrom_mem(self.a, 0, 2))[0]

    def read(self):
        return (self.regrd(0) >> 5) * 0.125

def main():
    i2 = I2C(1, freq = 100000)
    print(i2.scan())
    d = Temp(i2)

    while True:
        print("%.3f C" % d.read())
        time.sleep(.05)
Default I²C address 0x48 (0b1001000)
Current consumption (typ.) 5 mA
Vcc 3.3 V