micro:bit Python编程：添加radio变量ch编译报错求助

Hey there, let's sort out why your code is throwing errors when using a variable for the radio channel. The core issue here is the order of your radio commands!

The Problem in Your Code #

You're calling radio.on() before setting the channel with radio.config(channel=ch). On the micro:bit, once you turn the radio on, you can't modify its configuration anymore—any attempts to call radio.config() after radio.on() will trigger an error.

Corrected Code #

Here's how to adjust your code to make it work:

from microbit import *
import radio

# First set the channel using your variable
ch = 30
# Ensure ch stays within valid micro:bit radio channel range (0-83)
if 0 <= ch <= 83:
    radio.config(channel=ch)
else:
    # Fallback to a safe default if ch is out of bounds
    radio.config(channel=7)

# Now turn the radio on
radio.on()

# Rest of your program logic goes here...

Key Tips to Avoid Future Issues #

• Always run radio.config() before radio.on()—this is a strict rule for the micro:bit radio module.
• Keep your ch variable within the valid channel range: 0 to 83. Values outside this range will cause another error, so adding a quick check like the if statement above can save you headaches.
• If you need to change the channel while the program is running, you'll have to cycle the radio off and on again:

  radio.off()
  ch = 45  # Update channel with your external input value
  radio.config(channel=ch)
  radio.on()
  

内容的提问来源于stack exchange，提问作者Edson Sobreira