Upload MicroPython to Pico

Upload MicroPython to Pico | Generated by AI

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After flashing MicroPython onto your Raspberry Pi Pico (using the .uf2 file as described), you can upload and run a simple MicroPython program using a tool like Thonny IDE, which is beginner-friendly and widely used for MicroPython development. Below are the steps to set up MicroPython and upload a simple program to your Pico.

Prerequisites

MicroPython Flashed: You’ve already copied RPI_PICO-20250415-v1.25.0.uf2 to the RPI-RP2 drive, and the Pico has restarted (the RPI-RP2 drive should no longer appear).
USB Connection: The Pico is connected to your computer via a USB cable that supports data transfer.
Thonny IDE: Install Thonny if you haven’t already:
- Linux: Install Thonny using your package manager or download it from thonny.org.
```
sudo apt update
sudo apt install thonny
```
- Alternatively, use pip:
```
pip install thonny
```
- For Windows/macOS, download and install from thonny.org.

Step-by-Step Guide to Upload a Simple MicroPython Program

Connect the Pico and Open Thonny:
- Plug your Pico into your computer’s USB port.
- Open Thonny IDE.
Configure Thonny for MicroPython:
- In Thonny, go to Tools > Options > Interpreter (or Run > Select interpreter).
- Select MicroPython (Raspberry Pi Pico) from the interpreter dropdown.
- If the Pico’s serial port (e.g., /dev/ttyACM0 on Linux) doesn’t appear automatically:
  - Check available ports in the dropdown or run ls /dev/tty* in a terminal to identify the Pico’s port (usually /dev/ttyACM0 or similar).
  - Select the correct port manually.
- Click OK to save.
Verify MicroPython is Running:
- In Thonny’s Shell (bottom panel), you should see a MicroPython REPL prompt like:
```
>>> 
```
- Test it by typing a simple command, e.g.:
```
print("Hello, Pico!")
```
  Press Enter, and you should see the output in the Shell.

Write a Simple MicroPython Program:

In Thonny’s main editor, create a new file and write a simple program. For example, a program to blink the Pico’s onboard LED (on GPIO 25 for Pico, or “LED” for Pico W):

from machine import Pin
import time

# Initialize the onboard LED
led = Pin(25, Pin.OUT)  # Use "LED" instead of 25 for Pico W

# Blink the LED
while True:
    led.on()           # Turn LED on
    time.sleep(0.5)    # Wait 0.5 seconds
    led.off()          # Turn LED off
    time.sleep(0.5)    # Wait 0.5 seconds

Note: If using a Pico W, replace Pin(25, Pin.OUT) with Pin("LED", Pin.OUT).

Save the Program to the Pico:
- Click File > Save As.
- In the dialog, select Raspberry Pi Pico as the destination (not your computer).
- Name the file main.py (MicroPython runs main.py automatically on boot) or another name like blink.py.
- Click OK to save the file to the Pico’s filesystem.
Run the Program:
- Click the green Run button (or press F5) in Thonny to execute the program.
- Alternatively, if you saved it as main.py, reset the Pico (unplug and replug, or press the RESET button if available), and the program will run automatically.
- You should see the onboard LED blinking every 0.5 seconds.
Stop the Program (if needed):
- To stop the program, press Ctrl+C in Thonny’s Shell to interrupt the running script.
- To remove main.py from auto-running, delete it from the Pico:
  - In Thonny, go to View > Files, select the Pico’s filesystem, right-click main.py, and choose Delete.

Testing and Troubleshooting

No REPL Prompt: If Thonny doesn’t show the MicroPython REPL:
- Ensure the correct port is selected in the interpreter settings.
- Verify MicroPython flashed correctly. If not, reflash the .uf2 file as described earlier.
- Check the USB cable (must support data) and try a different port.
LED Not Blinking: Ensure the correct GPIO pin is used (25 for Pico, "LED" for Pico W). If it still doesn’t work, test the LED with a simple REPL command:
```
from machine import Pin
led = Pin(25, Pin.OUT)
led.on()
```
File Not Saving: Ensure Thonny is connected to the Pico and the interpreter is set to MicroPython (Raspberry Pi Pico).

Additional Tips

Using Other Tools: Besides Thonny, you can use rshell or ampy to manage files on the Pico:
```
pip install rshell
rshell --port /dev/ttyACM0
cp blink.py /pyboard/main.py
```
More Example Programs:
- Read a button press (e.g., on GPIO 14):
```
from machine import Pin
button = Pin(14, Pin.IN, Pin.PULL_UP)
while True:
    print(button.value())
```
- Control an external LED or other peripherals by adjusting the GPIO pin number.
Auto-Run: Saving a file as main.py makes it run automatically on boot. Use boot.py for setup code that runs before main.py.

If you encounter specific issues (e.g., port detection, errors in Thonny, or hardware problems), or want to try a different program, let me know, and I’ll guide you further!

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