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diff --git a/README.md b/README.md
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+Contains two scripts:
+    - Bash script generating rrd database and generating graphs from it
+    - Python script readding from MQTT and updating rrd database
+    - Settings for the Python script
+
+DEPENDENCIES:
+    - configparser
+    - paho
+    - rrdtool
+    kernel support ( amongst others (: ):
+        - CONFIG_USB_VIDEO_CLASS
+
+Steps to get going:
+    - Generate rrd file with ./generate_rrd_db.sh -c -i <rrd-file>
+    - Set up MQTT broker.
+    - Set up Raspberry Pi pico (Pico project in Micropython section)
+    - Fill in settings.cfg with your data
+    - Set up certificates (Check out Pico project for Bash script generating them)
+    - Run Python script.
+    - Set up cron job regenerating graphs with frequency to your liking.
+
+(So that I don't forget:)
+What is still missing:
+    - Python script should run as a daemon.
+    - Python script could generate more graphs based on averages from rrd database showing long term trends.
+    - Graph generation could be done with rrdcgi (not sure it is needed though)
+    - Documentation is lacking detailed step by step setup guide.
diff --git a/generate_rrd_db.sh b/generate_rrd_db.sh
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+#!/bin/bash
+
+RRD_DATABASE=""
+RRD_GRAPH=w1_graph.png
+# Base interval in seconds with which data will be fed into the database:
+STEP=15
+# One wire sensor address:
+ROM=00-055300000000  # TODO: update me with a real thing!
+# Seconds in a year: 31'536'000
+GRAPH=false
+CREATE=false
+
+function Help() {
+    # Display help
+    echo "Command generating graph from rrd database"
+    echo
+    echo "Syntax: generate_rrd [-h|-g|-c|-o|-i]"
+    echo "options:"
+    echo "-h     Print this help"
+    echo "-g     Create graph"
+    echo "-c     Create database"
+    echo "-i     Input rrd database file"
+    echo "-o     Output image, defaults to 'w1_graph.png'"
+    exit 0
+}
+
+
+# Create rrd database if not exist,
+# TODO: generate more graphs based on averages
+# Keep once in 5 minutes average, min and max for a month,
+# Keep once an hour for a year:
+function rrd_create() {
+    if test -f "$RRD_DATABASE"; then
+        echo "Database already exists, exiting."
+        exit 1
+    else
+      rrdcreate "$RRD_DATABASE" --step="$STEP" \
+      DS:temp:GAUGE:45:U:U \
+      RRA:AVERAGE:0.5:1:108000 \
+      RRA:AVERAGE:0.5:20:5400 \
+      RRA:MIN:0.5:20:5400 \
+      RRA:MAX:0.5:20:5400 \
+      RRA:AVERAGE:0.5:240:131400 \
+      RRA:MAX:0.5:240:131400 \
+      RRA:AVERAGE:0.5:240:131400
+    fi
+}
+
+# Generate graph image:
+rrd_graph() {
+    echo "Creating graph $RRD_GRAPH"
+    rrdtool graph "$RRD_GRAPH" --start -86400 --end now \
+      --vertical-label "Temperature C" \
+      --upper-limit 40 \
+      --lower-limit -30 \
+      -w 640 -h 480 \
+      DEF:temperature="$RRD_DATABASE":temp:AVERAGE \
+      LINE1:temperature#00FF00:"temperature C"
+}
+
+while getopts hgci:o: flag; do
+    case "${flag}" in
+        h) Help # Display help
+            exit;;
+        i) # Input rrd file
+            RRD_DATABASE=${OPTARG};;
+        o) # Output image 
+            RRD_GRAPH=${OPTARG};;
+        c) # Create rrd database
+            echo "Creating database ..."
+            CREATE=true;;
+        g) # Create graph
+            echo "Creating graph ..."
+            GRAPH=true;;
+        \?) # Invalid option
+            echo "Invalid option"
+            Help;;
+    esac
+done
+
+if [ -z "$RRD_DATABASE" ]
+then
+    echo "Please specify rrd database."
+    Help
+fi
+
+if [[ $CREATE == false ]] && [[ $GRAPH == false ]];then
+    echo "Specify either database creation (-c) or graph generation (-g) option"
+    Help
+fi
+
+if $CREATE; then
+    rrd_create
+fi
+
+if $GRAPH; then
+    rrd_graph
+fi
diff --git a/mqtt_to_rrd.py b/mqtt_to_rrd.py
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+"""
+Script reading from mqtt broker and writing to rrd database.
+"""
+#########################################################
+#                       IMPORTS                         #
+#########################################################
+
+import os
+import ssl
+from configparser import ConfigParser
+from time import time
+import rrdtool
+from paho.mqtt.client import Client as MQTTClient
+
+#########################################################
+#                       SETTINGS                        #
+#########################################################
+
+CONFIG_FILE = 'settings.cfg'
+USER = os.getlogin()
+RRD_DATABASE = f"/home/{USER}/w1_database.rrd"
+
+#########################################################
+#                           CODE                        #
+#########################################################
+
+
+SSL_SET = None
+CERT_DIR = None
+CA_CERT = None
+CERT_FILE = None
+KEY_FILE = None
+ONE_WIRE_UPPER = None
+ONE_WIRE_LOWER = None
+HOSTNAME = None
+PORT = None
+KEEPALIVE = None
+DATA_LENGTH_LIMIT = None
+TOPIC = None
+TIMEFORMAT = None
+Y_LIMIT = None
+X_LIMIT = None
+INTERVAL = None
+
+
+def get_settings(config_file):
+    """
+    Get settings from configparser.
+    """
+    cfg = ConfigParser(interpolation=None)
+    cfg.read(config_file)
+
+    global SSL_SET
+    global CERT_DIR
+    global CA_CERT
+    global CERT_FILE
+    global KEY_FILE
+    global ONE_WIRE_UPPER
+    global ONE_WIRE_LOWER
+    global HOSTNAME
+    global PORT
+    global KEEPALIVE
+    global DATA_LENGTH_LIMIT
+    global TOPIC
+    global TIMEFORMAT
+    global Y_LIMIT
+    global X_LIMIT
+    global INTERVAL
+    # SSL certificates:
+    SSL_SET = cfg.getboolean('Certificates', 'ssl')
+    CERT_DIR = cfg.get('Certificates', 'certificate_directory')
+    CA_CERT_PATH = os.path.join(
+            CERT_DIR,
+            cfg.get('Certificates', 'ca_crt')
+    )
+    CERT_FILE_PATH = os.path.join(
+            CERT_DIR,
+            cfg.get('Certificates', 'cert_file'),
+    )
+    KEY_FILE_PATH = os.path.join(
+            CERT_DIR,
+            cfg.get('Certificates', 'key_file')
+    )
+    CA_CERT = CA_CERT_PATH if CA_CERT_PATH else None
+    CERT_FILE = CERT_FILE_PATH if CERT_FILE_PATH else None
+    KEY_FILE = KEY_FILE_PATH if KEY_FILE_PATH else None
+
+    # One wire mapping:
+    ONE_WIRE_UPPER = cfg.get('Sensor_mapping', 'upper')
+    ONE_WIRE_LOWER = cfg.get('Sensor_mapping', 'lower')
+
+    # MQTT host:
+    HOSTNAME = cfg.get('Mqtt', 'hostname')
+    PORT = cfg.getint('Mqtt', 'port')
+    KEEPALIVE = cfg.getint('Mqtt', 'keepalive')
+
+    DATA_LENGTH_LIMIT = cfg.get('Main', 'data_length_limit')
+    TOPIC = cfg.get('Main', 'topic')
+    TIMEFORMAT = cfg.get('Main', 'timeformat')
+
+    # Plot settings:
+    Y_LIMIT = (
+        cfg.getint('Main', 'y_min'),
+        cfg.getint('Main', 'y_max')
+    )
+    X_LIMIT = cfg.getint('Main', 'x_limit')
+    INTERVAL = cfg.getint('Main', 'interval')
+
+
+class MyMQTTClient(MQTTClient):
+    """
+    MQTT client class on_message writing to rrd database.
+    """
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.data_limit = DATA_LENGTH_LIMIT
+        if SSL_SET:
+            self.tls_set(
+                ca_certs=CA_CERT,
+                certfile=CERT_FILE,
+                keyfile=KEY_FILE,
+                cert_reqs=ssl.CERT_REQUIRED,
+            )
+        self.connect(host=HOSTNAME, port=PORT, keepalive=KEEPALIVE)
+        self.bare_topic = TOPIC.strip("/#")
+        self.full_topic = f'{self.bare_topic}/{ONE_WIRE_UPPER}'
+        self.subscribe(self.full_topic)
+        self.on_message = self.onmessage
+        self.on_disconnect = self.ondisconnect
+
+    def ondisconnect(self, client):
+        print("Disconnected from MQTT")
+        client.loop_stop()
+
+    def on_connect(self, client, userdata, flags, rc):
+        print("Connected to MQTT, returncode: ", str(rc))
+        # Subscribing in on_connect() means that if we lose the connection and
+        # reconnect then subscriptions will be renewed.
+        client.subscribe("$SYS/#")
+
+    def onmessage(self, client, userdata, msg):
+        """
+        On message update rrd database.
+        """
+        temperature = msg.payload.decode("utf-8")
+        if msg.topic == self.full_topic:
+            now = time()  # TODO: pass timestamp in the message body
+
+            rrdtool.update(RRD_DATABASE, '%s:%s' % (now, temperature))
+
+
+def main():
+    """Main loop"""
+    get_settings(CONFIG_FILE)
+    client = MyMQTTClient()
+    client.loop_forever()
+
+
+if __name__ == '__main__':
+    main()
diff --git a/settings.cfg.example b/settings.cfg.example
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+[Main]
+data_length_limit = 10
+timeformat = %Y-%m-%d %H:%M:%S
+topic = temperature
+y_max = 51
+y_min = -20
+x_limit = 2000
+interval = 5000
+
+[Certificates]
+ssl = True
+certificate_directory =
+ca_crt =
+cert_file =
+key_file =
+
+[Sensor_mapping]
+upper =
+lower =
+
+[Mqtt]
+hostname =
+port = 8883
+keepalive = 60
+topic = temperature