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Do it yourself: Remote Controlled Micro:Bit Junkbot

In an earlier post, I showed how you could build a Micro:Bit controlled Junkbot. In this post I want to show a modification to it, to use one Micro:Bit to control the junkbot controlled by another Micro:Bit. A nice feature of the Micro:Bit using micropython, is it can send and receive simple messages via radio - so here is my take on it.

The first problem is the Python editor available on https://www.microbit.co.uk/ does not seem to work with the radio API. One solution to this is to change to the mu editor.


Two pieces of code are needed.

Sending Code for the 'remote' control:
Essentially it is set up to send two messages, via the built-in radio module, spinl or spinr depending on which button is pressed.

import radio
from microbit import button_a, button_b

radio.on()

while True:
   if button_a.is_pressed():
       radio.send('spinl')
   if button_b.is_pressed():

       radio.send('spinr')

Junkbot Code
This takes an adapted form of the previous Junkbot code to work by; on receiving spinl or spinr via the radio link; spin the motor clockwise or anticlockwise.
import radio
from microbit import pin8, pin12, sleep

def leftTurn(duration):
   pin8.write_digital(0)
   pin12.write_digital(1)
   sleep(duration)
   
def rightTurn(duration):
   pin8.write_digital(1)
   pin12.write_digital(0)
   sleep(duration)
   
def stopIt():
   pin8.write_digital(0)
   pin12.write_digital(0)

radio.on()
while True:
   incoming = radio.receive()
   if incoming == 'spinl':
        leftTurn(500)
        stopIt()
   if incoming == 'spinr':
        rightTurn(500)
        stopIt()








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