Скачать или смотреть Resolving readline() Issues in Python While Reading Data from Arduino

Discover how to effectively read data from Arduino in Python using `pyserial`. Learn to fix common issues with `readline()` that may arise when communicating between devices.
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Resolving readline() Issues in Python While Reading Data from Arduino

When working with an Arduino connected to a computer, it’s common to use the pyserial library in Python to read data sent from the Arduino. However, you might run into some frustrating issues, especially with the readline() method. Many users, including those on Windows, have reported encountering unexpected outputs when trying to read structured data from their Arduino devices.

In this guide, we will explore a common problem faced by users when receiving data from an Arduino via Python and provide step-by-step solutions to ensure smooth communication between the two.

The Problem: Unexpected Output in Python

Consider the scenario where you’re sending data from your Arduino to Python as follows:

Arduino Code

[[See Video to Reveal this Text or Code Snippet]]

When you use your Arduino's Serial Monitor, it displays the output correctly:

[[See Video to Reveal this Text or Code Snippet]]

However, upon attempting to read this data from Python, your output looks like this instead:

[[See Video to Reveal this Text or Code Snippet]]

This unexpected output can be disconcerting, but don’t worry! We’ll fix this.

Solution: Modify Your Python & Arduino Code

Step 1: Update the Arduino Code

You want to ensure that each line sent from the Arduino ends with a newline character and is printed in one go. This minimizes the chance of losing data integrity due to timing issues. Here’s how to modify your Arduino loop:

[[See Video to Reveal this Text or Code Snippet]]

Change: We utilize String() for concatenating the values and print everything in one statement with a newline at the end.

Step 2: Adjust the Python Code

Here’s a simplified and improved version of the Python script you need to use:

[[See Video to Reveal this Text or Code Snippet]]

Key Adjustments:

The code now calls strip() to remove any unwanted whitespace or newline characters from the output.

With these changes, you should now receive clean lines of data from your Arduino.

Final Thoughts

Communicating between different devices like an Arduino and a computer can sometimes lead to unexpected hurdles, especially when reading and interpreting data. However, by ensuring that your Arduino sends well-formatted strings and that your Python code calls the right methods to read those strings, you can achieve a seamless integration.

If you follow the adjustments provided above, you should be able to read data consistently and correctly. Happy coding!