Update README

README.org

@@ -1,38 +1,58 @@
 * Homeostasis
 
-Temperature and humidity sensor that communicates via MQTT. The project is implemented using a Wemos D1 mini ESP32 board with a DHT22 sensor.
+Temperature and humidity sensor that communicates via MQTT. The project is implemented using a Wemos D1 mini ESP32 board with a DHT22 shield.
+
+This specific shield needs to have the data line connected to a pin different to D4, as explained in [[https://blog.zs64.net/2018/02/fixing-the-wemos-d1-mini-dht22-shield][this blog post]].
 
 #+ATTR_HTML: :width 60%
-[[./result.png]]
+[[./board.jpg]]
 
 ** Pinout of the board
 
 #+ATTR_HTML: :width 40%
 [[./pinout.png]]
+
 ** Dependencies
+
 - [[https://github.com/adafruit/DHT-sensor-library][Adafruit DHT sensor library]]
 - [[https://github.com/adafruit/Adafruit_Sensor][Adafruit Unified Sensor Driver]]
 - [[https://github.com/marvinroger/async-mqtt-client][Async MQTT client]]
 - [[https://github.com/bblanchon/ArduinoJson][ArduinoJSON]]
+  
 ** Configuration
+
+In the data directory, there is a JSON file that allows the configuration of multiple values:
+
+- ssid: WiFi network name
+- psk: WiFi password
+- mqtt_host: IP address of the MQTT broker
+- mqtt_user: username that has write access on the MQTT broker
+- mqtt_password: password for the user that has write access on the MQTT broker
+- mqtt_port: port used by the MQTT broker
+- mqtt_topic: channel name
+- device_id: unique identifier of the sensor
+- sleep_time: time interval between each data transmission
+- connection_attempts: maximum connection attemps to the network
+
+The file needs to be renamed to config.json
+
 ** Deployment
 
-The software uses the Arduino framework and the development environment of [[https://platformio.org/][PlatformIO]], which offers better tools than the Arduino IDE.
-
-1. Upload the configuration file to the board:
+The software uses the Arduino framework and the development environment of [[https://platformio.org/][PlatformIO]], which offers better tooling than the official Arduino IDE.
 
+*** Generate compilation database
+#+begin_src sql
+pio run -t compiledb
+#+end_src
+*** Upload the configuration file to the board
 #+begin_src shell
 pio run -t uploadfs
 #+end_src
-
-2. Compile the project
-
+*** Compile the project
 #+begin_src shell
 pio run -t compile
 #+end_src
-
-3. Upload firmware
-
+*** Upload firmware
 #+begin_src shell
 pio run -t upload
 #+end_src