With the help of these two files, you can turn your joy car and another micro:bit into a remote-controlled car. Load the rc_joycar.py on the micro:bit of your joy-car and the rc_remote.py on the micro:bit you use as a remote control. Tilt the micro:bit you use as a remote control in the direction you want to drive and your joy car will drive in that direction. On button A you use the horn. Button B turns on the light.

# Import of the required modules
import microbit
import radio

# Switching on the radio hardware
radio.on()

# Definition of the variables for data transmission
data0 = "0"
data1 = "0"
data = "00"

# Query loop
while True:
    # read out the values of the acceleration sensor
    a = microbit.accelerometer.get_values()

    # Assign the letters to a direction and store in data0
    # micro:bit tilted to the left and not forward beyond the threshold value
    if a[0] >= 300 and a[1] <= 300:
        data0 = "l"
    # micro:bit tilted to the right and not forward beyond the threshold value
    elif a[0] <= -300 and a[1] <= 300:
        data0 = "r"
    # micro:bit tilted forward and not over threshold to the side
    elif a[1] <= -300 and a[0] >= -300 and a[0] <= 300:
        data0 = "f"
    # micro:bit tilted backwards
    elif a[1] >= 300:
        data0 = "b"
    # else 0
    else:
        data0 = "0"

# Assign the letters to a button and store in data1
    if microbit.button_a.is_pressed() == 1 and microbit.button_b.is_pressed() == 0:
        data1 = "a"
    elif microbit.button_a.is_pressed() == 0 and microbit.button_b.is_pressed() == 1:
        data1 = "b"
    elif microbit.button_a.is_pressed() == 1 and microbit.button_b.is_pressed() == 1:
        data1 = "c"
    else:
        data1 = "0"
    # combine data0 and data1 and store them in data
    data = data0 + data1
    # send data
    radio.send(data)
# Import of the required modules
from microbit import *
import neopixel
import radio
import music
# Initalization of the RGB LEDs
np = neopixel.NeoPixel(pin0, 8)

# Turn on the radio hardware
radio.on()

# Predefinitions for lighting
headlights = (0, 3)
backlights = (5, 6)
led_white = (60, 60, 60)
led_red = (60, 0, 0)
led_off = (0, 0, 0)

# Function to control the motors
def drive(PWM0, PWM1, PWM2, PWM3):
    i2c.write(0x70, b'\x02' + bytes([PWM0]))
    i2c.write(0x70, b'\x03' + bytes([PWM1]))
    i2c.write(0x70, b'\x04' + bytes([PWM2]))
    i2c.write(0x70, b'\x05' + bytes([PWM3]))

# Switch on low beam
def lightsON():
    for x in headlights:
        np[x] = led_white
    for x in backlights:
        np[x] = led_red
    np.show()

# Switch off light
def lightsOFF():
    for x in headlights:
        np[x] = led_off
    for x in backlights:
        np[x] = led_off
    np.show()


# Control loop
while True:
    # Reception via radio hardware is stored in the variable incoming
    incoming = radio.receive()
    # if incoming is not None (empty) then:
    if incoming is not None:
        # Query the 1st character for the direction
        if incoming[0] == "l":
            drive(0, 0, 40, 255)
        elif incoming[0] == "r":
            drive(40, 255, 0, 0)
        elif incoming[0] == "f":
            drive(40, 255, 40, 255)
        elif incoming[0] == "b":
            drive(255, 40, 255, 40)
        else:
            drive(0, 0, 0, 0)

        # Switching the reversing light on and off
        if incoming[0] == "b":
            np[4] = (led_white)
            np.show()
        else:
            np[4] = (led_off)
            np.show()
        # Query of the 2nd character for the functions (light and horn).
        if incoming[1] == "a":
            music.play("c4:1", pin=pin16)
        elif incoming[1] == "b":
            lightsON()
        elif incoming[1] == "c":
            lightsON()
        else:
            lightsOFF()
    # if incoming = None, then the joy-car is parked.
    # This is usually the case when the joy-car is out of range
    # of the remote control or when the remote control is off.
    else:
        drive(0, 0, 0, 0)
        for x in range(0, 8):
            np[x] = (50, 0, 0)
        np.show()