Pico Getting Started

Text tutorial

Introduction

Raspberry Pi Pico Basics

MicroPython series

Install Thonny IDE

In order to facilitate the development of Pico/Pico2 boards using MicroPython on a computer, it is recommended to download the Thonny IDE

• Download Thonny IDE and follow the steps to install, the installation packages are all Windows versions, please refer to Thonny's official website for other versions
  • Thonny IDE official download link
  • Thonny IDE download link
  • Thonny official website
• After installation, the language and motherboard environment need to be configured for the first use. Since we are using Pico/Pico2, we select the Raspberry Pi option for the motherboard environment

• Configure MicroPython environment and choose Pico/Pico2 port
  
  • Connect Pico/Pico2 to your computer first, and in the lower right corner of Thonny left-click on the configuration environment option --> select Configture interpreter
  • In the pop-up window, select MicroPython (Raspberry Pi Pico), and choose the corresponding port

• Click OK to return to the Thonny main interface, download the corresponding firmware library and burn it to the device, and then click the Stop button to display the current environment in the Shell window
  • Pico firmware library
  • Pico2 firmware library
• How to download the firmware library for Pico/Pico2 in windows: After holding down the BOOT button and connecting to the computer, release the BOOT button, a removable disk will appear on the computer, copy the firmware library into it
• How to download the firmware library for RP2040/RP2350 in windows: After connecting to the computer, press the BOOT key and the RESET key at the same time, release the RESET key first and then release the BOOT key, a removable disk will appear on the computer, copy the firmware library into it (you can also use the Pico/Pico2 method)
  

Details

• 【MicroPython】 machine.Pin Function
• 【MicroPython】 machine.PWM Function
• 【MicroPython】 machine.ADC Function
• 【MicroPython】 machine.UART Function
• 【MicroPython】 machine.I2C Function
• 【MicroPython】 machine.SPI Function
• 【MicroPython】 rp2.StateMachine
  

C/C++ series

For C/C++, it is recommended to use Pico VS Code for development. This is a Microsoft Visual Studio Code extension designed to make it easier for you to create, develop, and debug projects for the Raspberry Pi Pico series development boards. No matter if you are a beginner or an experienced professional, this tool can assist you in developing Pico with confidence and ease. Here's how to install and use the extension.

• Official website tutorial: https://www.raspberrypi.com/news/pico-vscode-extension/
• This tutorial is applicable to Raspberry Pi Pico, Pico2 and the RP2040 and RP2350 series development boards developed by our company
• The default development environment is Windows. For other environments, please refer to the official website tutorial for installation

Install VSCode

1. Firstly, click to download pico-vscode package, unzip and open the package, double-click to install VSCode
   
   Note: If vscode is already installed, check if the version is v1.87.0 or higher
   

Install extension

1. Click on EXTENSIONS, select Install from VSIX
   
2. Select the package with vsix suffix, click Install
   
3. Then vscode will automatically install Raspberry Pi Pico and its dependent extensions. You can click Refresh to view the installation progress
   
4. The bottom right corner shows installation completed, close vscode
   

Configure extension

1. Open the directory C:\Users\username and copy the entire .pico-sdk to that directory
   
2. The copy is completed
   
3. Open VSCode and configure various paths in the Raspberry Pi Pico extension
   
   The configuration is as follows:

   Cmake Path:
   ${HOME}/.pico-sdk/cmake/v3.28.6/bin/cmake.exe
   
   Git Path:
   ${HOME}/.pico-sdk/git/cmd/git.exe    
   
   Ninja Path:
   ${HOME}/.pico-sdk/ninja/v1.12.1/ninja.exe
   
   Python3 Path:
   ${HOME}/.pico-sdk/python/3.12.1/python.exe             
   

New project

1. Configuration is completed, then create a new project. First enter the project name, select the path, and click Create to create the project
   To test the official example, you can click Example next to the project name to select
   
2. The project was created successfully
   
3. Select SDK version
   
4. Select Yes for advanced configuration
   
5. Select the cross-compilation chain, 13.2.Rel1 is for ARM cores, RISCV.13.3 is for RISCV cores, and you can choose one of them according to your needs
   
6. Selects Default (the path configured earlier) for CMake version
   
7. Select Default for Ninja version
   
8. Select development board
   
9. Click Complie to compile
   
10. The uf2 format file is successfully compiled
    

Import project

1. The Cmake file for importing the project cannot have Chinese (including comments), otherwise it may cause import failure
2. To import your own project, you need to add a line of code to the Cmake file to switch between pico and pico2 normally, otherwise even if pico2 is selected, the compiled firmware will still be suitable for pico
   
   

   set(PICO_BOARD pico CACHE STRING "Board type")
   

Update extension

1. The extension version in the offline package is 0.15.2, and you can also choose to update to the latest version after the installation is complete
   

Arduino IDE series

Install Arduino IDE

1. First, go to Arduino official website to download the installation package of the Arduino IDE.
   
2. Here, you just need to select to download.
   
3. Once the download is complete, click Install.
   Notice: During the installation process, it will prompt you to install the driver, just click Install
   

Arduino IDE interface

1. After the first installation, when you open the Arduino IDE, it will be in English. You can switch to other languages in File --> Preferences, or continue using the English interface.
   
2. In the Language field, select the language you want to switch to, and click OK.
   
   

Install Arduino-Pico Core in the Arduino IDE

1. Open the Arduino IDE, click on the file in the top left corner, and select Preferences
   
2. Add the following link to the attached board manager URL, and then click OK

   https://github.com/earlephilhower/arduino-pico/releases/download/4.0.2/package_rp2040_index.json

   
   Note: If you already have an ESP32 board URL, you can use a comma to separate the URLs as follows:

   https://dl.espressif.com/dl/package_esp32_index.json,https://github.com/earlephilhower/arduino-pico/releases/download/4.0.2/package_rp2040_index.json

3. Click Tools > Development Board > Board Manager > Search pico, as my computer has already been installed, it shows that it is installed
   

First upload of the program

1. Press and hold the BOOTSET button on the Pico board, connect the pico to the USB port of the computer via the Micro USB cable, and release the button after the computer recognizes a removable hard disk (RPI-RP2).
   
2. Download the program and open D1-LED.ino under the arduino\PWM\D1-LED path
3. Click Tools --> Port, remember the existing COM, do not click this COM (the COM displayed is different on different computers, remember the COM on your own computer)
   
4. Connect the power board to the computer using a USB cable. Then, go to Tools > Port. For the first connection, select uf2 Board. After uploading, when you connect again, an additional COM port will appear
   
5. Click Tools > Development Board > Raspberry Pi Pico > Raspberry Pi Pico or Raspberry Pi Pico 2
   
6. After setting it up, click the right arrow to upload the program
   
   

• If issues arise during this period, and if you need to reinstall or update the Arduino IDE version, it is necessary to uninstall the Arduino IDE completely. After uninstalling the software, you need to manually delete all contents within the C:\Users\[name]\AppData\Local\Arduino15 folder (you need to show hidden files to see this folder). Then, proceed with a fresh installation.

Open source demos

MircoPython video demo (github)
MicroPython firmware/Blink demos (C)
Raspberry Pi official C/C++ demo (github)
Raspberry Pi official micropython demo (github)
Arduino official C/C++ demo (github)

Example Experiments

Download the Demo to your computer desktop to conduct some interesting experiments.

External LED experiment

• Connect the hardware according to the figure below, connect the Micro USB connected to the computer, open the python file in the demo Lesson-5 External LED in Thonny, and you can see that the red light is flashing when you run the demo.
  
• Precautions for use: The longer pin of the LED is the positive pole, the shorter one is the negative pole, the negative pole should be connected to GND, the positive pole should be connected to the GPIO output port, and the resistor must be connected when using.
  

• Code analysis

led_external = machine.Pin(15, machine.Pin.OUT) #Set GP15 to output mode
while True: 
   led_external.toggle() #Change the state of the LED light every 5 seconds
   utime.sleep(5)

Traffic Light System experiment

• Connect the hardware according to the figure below, connect the Micro USB connected to the computer, open the python file in the demo Lesson-9 Traffic-Light-System in Thonny, run the demo to see the traffic lights running normally, and the buzzer will be triggered when the button is pressed.
  
• Precautions for use: The longer pin of the LED is the positive pole, the shorter pin is the negative pole, the negative pole should be connected to GND, the positive pole should be connected to the GPIO output port, and the resistor must be connected when using. The red wire of the buzzer is connected to the GPIO port output, and the black wire is connected to GND.
  

• Code analysis

def button_reader_thread():  #Detect if a button is pressed
   global button_pressed 
   while True:
       if button.value() == 1: 
           button_pressed = True
           
_thread.start_new_thread(button_reader_thread, ()) #Use the thread to detect keystrokes
while True:
   if button_pressed == True: #If the button is pressed, the red light lights up and the buzzer alarms
       led_red.value(1) 
       for i in range(10): 
           buzzer.value(1) 
           utime.sleep(0.2) 
           buzzer.value(0) 
           utime.sleep(0.2) 
       global button_pressed 
       button_pressed = False 
   led_red.value(1)  #In normal circumstances, when the light turns from red to green, the yellow light will be on for two seconds, then the yellow light and red light will go off, and the green light will be on
   utime.sleep(5)     #When the light turns from green to red, the green light goes off first, the yellow light is on for two seconds, and then the red light is on
   led_amber.value(1) 
   utime.sleep(2) 
   led_red.value(0) 
   led_amber.value(0) 
   led_green.value(1) 
   utime.sleep(5) 
   led_green.value(0) 
   led_amber.value(1) 
   utime.sleep(5) 
   led_amber.value(0)

Burglar Alarm LED Buzzer experiment

• Connect the hardware according to the figure below, connect the Micro USB connected to the computer, open the python file in the demo Lesson-14 Burglar Alarm LED Buzzer in Thonny, run the demo and you can see that when you move in front of the Passive infrared sensor, the LED light will flash and the buzzer will sound an alarm.
  

Precautions for use: The middle pin of the Passive infrared sensor is the data output pin, and the pins on both sides can be connected to VCC and GND respectively.

• Code analysis

def pir_handler(pin):  #Interrupt handling function, the buzzer sounds, the LED rapidly flashes
   print("ALARM! Motion detected!") 
   for i in range(50): 
       led.toggle() 
       buzzer.toggle() 
       utime.sleep_ms(100)
sensor_pir.irq(trigger=machine.Pin.IRQ_RISING, handler=pir_handler) #Turn on the interrupt, and when the human sensor detects an exception, it will enter the interrupt handling function for processing
while True:  #If there is no exception, the state of LDE will be changed every 5 seconds
   led.toggle() 
   utime.sleep(5)

Potentiometer experiment

• Connect the hardware according to the figure below, connect the Micro USB connected to the computer, open the python file in the demo Lesson-16 Potentiometer in Thonny, run the demo, and rotate the potentiometer to see that the voltage value printed out in the Sheel window is also changing.
  

Precautions for use: The middle pin of the Potentiometer is the data output pin, and the pins on both sides can be connected to VCC and GND respectively.

• Code analysis

potentiometer = machine.ADC(26) #Use GP26 as the analog signal collection pin
conversion_factor = 3.3 / (65535)
while True:
   voltage = potentiometer.read_u16() * conversion_factor #Format the collected data and convert it into a voltage value
   print(voltage) #Print the voltage information, the voltage value will change as the sliding varistor rotates
   utime.sleep(2)

WS2812 experiment

• Connect the hardware according to the figure below, connect the Micro USB connected to the computer, open the WS2812_RGB_LED.py file in the demo Lesson-25 WS2812 in Thonny, run the demo to see the RGB colors of blue, red, green, and white at once.
  

• Code analysis

#This code uses the state machine mechanism, the following code is a decorator, in which we can initialize the hardware, set the level of the pins, etc.
#label("bitloop") We can define labels in the code to facilitate our execution by jumping to them.
#jmp(not_x,"do_zero") When x=0, we adjust to the label "do_zero".
#nop() .set(0) [T2 - 1] When x=0, it will jump here to execute.
@asm_pio(sideset_init=PIO.OUT_LOW, out_shiftdir=PIO.SHIFT_LEFT, autopull=True, pull_thresh=24)
def ws2812():
   T1 = 2
   T2 = 5
   T3 = 1
   label("bitloop")
   out(x, 1)               .side(0)    [T3 - 1] 
   jmp(not_x, "do_zero")   .side(1)    [T1 - 1] 
   jmp("bitloop")          .side(1)    [T2 - 1] 
   label("do_zero")
   nop()                   .side(0)    [T2 - 1]

# Create the StateMachine with the ws2812 program, outputting on Pin(22).
sm = StateMachine(0, ws2812, freq=8000000, sideset_base=Pin(0)) #Create a state machine
# Start the StateMachine, it will wait for data on its FIFO.
sm.active(1) #Start state machine
# Display a pattern on the LEDs via an array of LED RGB values.
ar = array.array("I", [0 for _ in range(NUM_LEDS)])
print(ar)
print("blue")
for j in range(0, 255): 
   for i in range(NUM_LEDS): 
       ar[i] = j 
   sm.put(ar,8)  The method of #put() is to put the data into the output FIFO of the state machine
   time.sleep_ms(5)

LCD1602 I2C experiment

• Connect the hardware according to the figure below, connect the Micro USB connected to the computer, open the python file in the demo Lesson-21 LCD1602 I2C in Thonny, save the RGB1602.py file as a Raspberry Pi Pico, and run the Choose_ Color.py to see a different color switch every 5 seconds; run Discoloration.py file to see the RGB color gradient effect.

• Code analysis

Choose_Color.py

#Define color
rgb9 = (0,255,0) #Green
lcd.setCursor(0, 0) #Set cursor position
# print the number of seconds since reset:
lcd.printout("Waveshare") #Write characters
lcd.setCursor(0, 1) #Set the cursor position to the second row and the zero column
lcd.printout("Hello,World!") #Write characters
lcd.setRGB(rgb1[0],rgb1[1],rgb1[2]); #Set the backlight

Discoloration.py

t=0
while True:
 
   r = int((abs(math.sin(3.14*t/180)))*255); #RGB changes over time
   g = int((abs(math.sin(3.14*(t+60)/180)))*255);
   b = int((abs(math.sin(3.14*(t+120)/180)))*255);
   t = t + 3;
   lcd.setRGB(r,g,b); #Reset the RGB value
# set the cursor to column 0, line 1
   lcd.setCursor(0, 0) #Navigate to the first row and the zero column
# print the number of seconds since reset:
   lcd.printout("Waveshare") #Write characters
   lcd.setCursor(0, 1) #Navigate to the second row and the zero column
   lcd.printout("Hello,World!") #Write characters
   time.sleep(0.3)