A simple BBC Micro:bit script that allows you to send radio messages to another Micro:bit that is running this same script

microbit-messenger.py

from microbit import *
import radio

# --- CONFIG ---
# Deadzone
deadzone = 350
# Scroll Speed (ms)
scrollspeed = 500

current = 1
characters = [" ", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", " "]
message = []
space = Image("00000:"
              "00000:"
              "00000:"
              "90009:"
              "99999")
newMessage = Image("05950:"
                   "50505:"
                   "95059:"
                   "99599:"
                   "99999")

tick = Image("00000:"
             "00009:"
             "00090:"
             "90900:"
             "09000")

radio.on()

def drawChar():
    if characters[current] == " ":
        display.show(space)
    else:
        display.show(characters[current])

def appendCurrent():
    if button_a.is_pressed():
        message.append(characters[current])
        print(''.join(message))
        display.show(Image().invert())
        sleep(scrollspeed)
    elif button_b.is_pressed():
        radio.send(''.join(message))
        message = []
        current = 1
        display.show(tick)
        sleep((scrollspeed * 2))

def checkForMessages():
    incoming = radio.receive()
    if incoming:
        display.show(newMessage)
        sleep(250)
        display.clear()
        sleep(250)
        display.show(newMessage)
        sleep(250)
        display.clear()
        sleep(250)
        display.show(newMessage)
        sleep(250)
        display.clear()
        sleep(250)
        display.show(newMessage)
        sleep(250)
        display.clear()
        sleep(250)
        display.scroll(incoming)

while True:
    reading = accelerometer.get_x()
    checkForMessages()
        
    if reading > deadzone:
        if current < (len(characters) - 1):
            current = current + 1
        drawChar()
        appendCurrent()
        sleep(scrollspeed)
    elif reading < (deadzone * -1):
        if current > 0:
            current = current - 1
        drawChar()
        appendCurrent()
        sleep(scrollspeed)
    else:
        drawChar()
        appendCurrent()