Script and Tests

Script: button_led_blink_with_plot

  • Right-click button_led_blink_with_plot.hex and select Save link as... to download it.

button_led_blink_with_plot.hex

  • Go to python.microbit.org/v/2.
  • Click Load/Save and then drag the file you just downloaded and drop it on the gray box in the Load section.  
  • Click the Flash button to load the script into the micro:bit.
  • Click Disconnect.


Tests

  • Go to cyberscope.parallax.com and click Connect.
  • Wait until the plotted dots reach (or wrap back around to) somewhere in the 2k to 4k range.
  • Press and hold the pushbutton for about six blinks.
  • Verify that your plot resembles this.  


NOTE: Before the first pushbutton press, you might notice the red Ch2 voltage trace is plotting irregularly in the 0.5 to 1.5 V range.  That’s because the LED pin is a floating input that has not been set to low or high by pin13.write_digital(0) or pin13.write_digital(1).

Also verify the following:

  • While the button is not held down:
    • The black ch0 trace connected to the pushbutton should repeatedly plot points close to 0 V along the bottom of the plot area.  
    • The red ch2 trace connected to the LED should also plot points close to 0 V along the bottom of the plot.  
  • While the button is held down:
    • The black ch0 trace should plot points at around 3.3 V.
    • The red ch2 trace should plot the on signals in the 2.5 to 3.3 V neighborhood, and off signals at 0 V, should continue to repeat while the button is pressed and held down.