Bikenetv2.1_lim.py

from microbit import *
import radio

xImage = Image("90009:"
               "09090:"
               "00900:"
               "09090:"
               "90009")

radioMap = {"left": b'\xF0', "right": b'\x0F',
            "stop": b'\xFF', "lost":  b'\x3C',
            "leader": b'\xAA', "denied": b'\x55',
            "go": b'\x00'}

inverseRadioMap = {radioMap["left"]: Image.ARROW_W, radioMap["right"]: Image.ARROW_E,
                   radioMap["stop"]: xImage,        radioMap["lost"]:  Image.SAD,
                   radioMap["go"]: "G"}

networkID = 0

def notifyUser():
    pin0.write_digital(1)
    sleep(200)
    pin0.write_digital(0)
    sleep(2016)

def notifyLost():
    pin0.write_digital(1)
    sleep(3000)
    pin0.write_digital(0)

def displayCross():
    for n in range(0, 3):
        display.show(xImage)
        sleep(200)
        display.clear()
        sleep(200)

def clearQueue():
    for n in range(0, 3):
        radio.receive_bytes()
        sleep(10)

def canBecomeLeader():
    radio.send_bytes(radioMap["leader"])

    counter = 0

    while True:
        messageCode = radio.receive_bytes()

        if messageCode == radioMap["denied"]:
            return False

        if counter >= 100:
            return True

        counter += 1

        sleep(10)

def selectNetwork():
    global networkID
    currentID = networkID
    display.show("?")
    while True:
        if button_a.is_pressed() and button_b.is_pressed():
            networkID = currentID
            display.scroll("Chan." + str(networkID))
            break
        elif button_a.is_pressed():
            currentID = (currentID - 1) % 10
            display.show(str(currentID))
        elif button_b.is_pressed():
            currentID = (currentID + 1) % 10
            display.show(str(currentID))
        sleep(163)

isLeader = False

def holdingState():
    global isLeader

    leaderCounter = 0
    followerCounter = 0

    while True:

        if button_a.is_pressed() and button_b.is_pressed():
            if followerCounter > 0:
                followerCounter = 0

            leaderCounter += 1

        elif button_a.is_pressed():
            if leaderCounter > 0:
                leaderCounter = 0

            followerCounter += 1

        else:
            leaderCounter = 0
            followerCounter = 0

        if leaderCounter >= 20:
            isLeader = canBecomeLeader()
            if isLeader:
                display.scroll("LEADER")
            else:
                displayCross()
                display.scroll("GUEST")
            break
        elif followerCounter >= 20:
            display.scroll("GUEST")
            isLeader = False
            break

        sleep(100)


### PROGRAM EXECUTION ###

selectNetwork()

radio.on()
radio.config(length = 1, channel = networkID, power = 7)

display.show("?")

holdingState()

clearQueue()

stopped = False

if isLeader:
    while True:

        messageCode = radio.receive_bytes()

        if messageCode != None:
            if messageCode == radioMap["leader"]:
                radio.send_bytes(radioMap["denied"])
            elif messageCode == radioMap["lost"]:
                try:
                    display.clear()
                    display.show(inverseRadioMap[messageCode])
                    notifyLost()
                    continue
                except KeyError:
                    sleep(200)
                    continue
            else:
                sleep(200)
                continue

        elif button_a.is_pressed() and button_b.is_pressed():
            if not stopped:
                display.clear()
                display.show(xImage)
                radio.send_bytes(radioMap["stop"])
                stopped = True
            else:
                display.clear()
                display.show("G")
                radio.send_bytes(radioMap["go"])
                stopped = False

        elif button_a.is_pressed():
            display.show(Image.ARROW_W)
            radio.send_bytes(radioMap["left"])

        elif button_b.is_pressed():
            display.show(Image.ARROW_E)
            radio.send_bytes(radioMap["right"])

        else:
            sleep(200)
            continue

        sleep(2000)
        display.clear()


else:
    while True:

        if button_a.is_pressed() and button_b.is_pressed():
            display.show(inverseRadioMap[radioMap["lost"]])
            radio.send_bytes(radioMap["lost"])
            sleep(5000)
            display.clear()

        messageCode = radio.receive_bytes()

        if messageCode != None:
            if messageCode == radioMap["lost"]:
                display.show(inverseRadioMap[messageCode])
                notifyLost()
            else:
                try:
                    display.show(inverseRadioMap[messageCode])
                    notifyUser()
                except KeyError:
                    sleep(200)
                    continue

        sleep(200)