The laboratory experiment aims to explore the possibilities of creating extensions for Pico/Pico 2 based on the use of the SPI communication protocol for interfacing with the Nokia LCD, as well as the use of the analog/digital converter in the structure of the RP2040/RP2350 microcontrollers for acquiring data from soil humidity sensors. For measuring air humidity, the DHT11/22 sensor is introduced. Examples are made with the Nokia 5110 display system based on the Philips PCD8544 controller and the MicroPython library named pcd8544_fb.py. At the end of the lab, detailed information will be available regarding the implementation of control systems for environmental parameters. and Underground Farming
Hardware: Platforma Raspberry Pi Pico/Pico 2, DHT22, Controller Nokia 5110, breadboard, potentiometru 10k, sensor soil humidity, fotorezistente, water pump. Software : MicroPython Nokia 5110 PCD8544 84x48 LCD 
MicroPython lib module for Nokia 5110 1. Pico - test interconectare LCD Nokia 5110 2. Pico LCD - display data from the A/D converter 3. Pico LCD - monitoring data from soil humidity sensor/photoresistor 4. Pico smart farm - reglare automata soil humidity ---------------------------------------------------------------- 5. Vizualizare date sensor DHT22 6. Display DHT22 sensor data on the Nokia 5110 LCD 
Extensions for the Pico platform can use communication protocols such as SPI, UART, I2C depending on distances, volume and the required transfer speeds. Display systems require high transfer speeds, and the volume of data in graphic mode is considerable. In these situations, the extensions use the SPI protocol which employs the signals shown below: 
The famous early Nokia phones used an LCD-Nokia 5110 based on the Philips PCD8544 controller, making it possible to develop an extension for the Pico, represented in the following figure: 
The interconnection between Nokia 5110 and Pico can be carried out on a breadboard according to the following schematic:  The correct interconnection of the components allows the visualization of the data on the LCD using example program no. 1. The analog/digital conversion module present in the RP2040 structure can be explored by connecting a potentiometer to the ADC0 input according to the previous schematic. It can provide a voltage level between 0-3.3V. Correct execution of example program no. 2 allows displaying this data on the LCD formatted to 2 decimals. Testing the operation of the humidity/light sensor can be carried out using example program no. 3.  Details about the MicroPython classes for SPI and ADC: 
1. Using example program no.1, add a Python sequence that will allow determining the limit positions for text display; . 2. Using example program no. 3, create an application that will allow displaying the processor temperature on the LCD; 3. Create a program that will allow determining the concentration of salt added into a glass of water; 4. Using a photoresistor, create a program to control the lighting level for plants. 5. Create a program that will turn on the red LED/water pump motor if the soil humidity of a plant is less than 20%.
- Dezvoltarea spatial enclosures for plant growth.> - Dezvoltarea universului Urban-agricultura . - Development of IoT with analog sensors ; - Development of portable intelligent instrumentation; - Development of systems for growing plants in greenhouses; 
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