EasyGreenHouse – Teil 3 – Befehle

sudo sed -i -e '$a dtoverlay=w1-gpio' /boot/config.txt

sudo raspi-config

sudo modprobe w1-gpio

sudo modprobe w1-therm

cd /sys/bus/w1/devices/

ls

cd [SENSORBEZEICHNUNG z.B. 28-239a3d1e64ff]

cat w1_slave

nano DS18B20classfile.py

Skript einfügen:

import os
import glob
import time


class DS18B20:

    def __init__(self):
        os.system('modprobe w1-gpio')
        os.system('modprobe w1-therm')
        base_dir = '/sys/bus/w1/devices/'
        device_folder = glob.glob(base_dir + '28*')
        self._count_devices = len(device_folder)
        self._devices = list()
        i = 0
        while i < self._count_devices:
            self._devices.append(device_folder[i] + '/w1_slave')
            i += 1

    def device_names(self):
        names = list()
        for i in range(self._count_devices):
            names.append(self._devices[i])
            temp = names[i][20:35]
            names[i] = temp
        return names

    def _read_temp(self, index):
        f = open(self._devices[index], 'r')
        lines = f.readlines()
        f.close()
        return lines

    def tempC(self, index=0):
        lines = self._read_temp(index)
        retries = 5
        while (lines[0].strip()[-3:] != 'YES') and (retries > 0):
            time.sleep(0.1)
            lines = self._read_temp(index)
            retries -= 1
        if retries == 0:
            return 998
        equals_pos = lines[1].find('t=')
        if equals_pos != -1:
            temp = lines[1][equals_pos + 2:]
            return float(temp) / 1000
        else:
            return 999  # error

    def device_count(self):
        return self._count_devices

Codequelle: AZ-Delivery

nano DS18B20multiple.py

Skript einfügen:

import time
from DS18B20classfile import DS18B20

degree_sign = u'\xb0' # degree sign
devices = DS18B20()
count = devices.device_count()
names = devices.device_names()

print('[press ctrl+c to end the script]')
try: # Main program loop
    while True:
        i = 0
        print('\nReading temperature, number of sensors: {}'
                                                         .format(count))
        while i < count:
            container = devices.tempC(i)
            print('{}. Temp: {:.3f}{}C, {:.3f}{}F of the device {}'
                                .format(i+1, container, degree_sign,
                                container * 9.0 / 5.0 + 32.0, degree_sign,
                                names[i]))
            i = i + 1

        time.sleep(1)

# Scavenging work after the end of the program
except KeyboardInterrupt:
    print('Script end!')

Codequelle: AZ-Delivery

python3 DS18B20multiple.py