pnLED.py

##################
#### pnLED.py ####
##################

# This code is ported from Raspberry Pi to Intel Edison.
# LEDs are activated in active-low signal!

from Pubnub import Pubnub
import mraa ## Import libmraa library

G_LED = mraa.Gpio(19) ## Initialize GPIO Pin MRAA19 as Green LED
Y_LED = mraa.Gpio(20) ## Initialize GPIO Pin MRAA20 as Yellow LED
R_LED = mraa.Gpio(21) ## Initialize GPIO Pin MRAA21 as Red LED

G_LED.dir(mraa.DIR_OUT) ## Setup GPIO Pin MRAA19 to OUT - Green
Y_LED.dir(mraa.DIR_OUT) ## Setup GPIO Pin MRAA20 to OUT - Yellow
R_LED.dir(mraa.DIR_OUT) ## Setup GPIO Pin MRAA21 to OUT - Red

G_LED.write(1) ## Turn off GPIO pin MRAA19 - Green
Y_LED.write(1) ## Turn off GPIO pin MRAA20 - Yellow
R_LED.write(1) ## Turn off GPIO pin MRAA21 - Red

# Enter your PubNub Publish Key and use the Market Order Demo Subscribe Key
pubnub = Pubnub(publish_key="YOUR PUB KEY", subscribe_key="sub-c-4377ab04-f100-11e3-bffd-02ee2ddab7fe", ssl_on=False)

# Listen for Messages on the Market Order Channel
channel = 'pubnub-market-orders'

def callback(message, channel):
    print(message['order_quantity']) # Use the Order Quantity value as the LED trigger
    
    # Reset LEDs to OFF
    G_LED.write(1)
    Y_LED.write(1)
    R_LED.write(1)
    
    if (message['order_quantity'] >= 100) and (message['order_quantity'] < 200):
        G_LED.write(0) # Turn on GREEN
    elif (message['order_quantity'] >= 200) and (message['order_quantity'] < 400):
        Y_LED.write(0) # Turn on YELLOW
    elif (message['order_quantity'] >= 400):
        R_LED.write(0) # Turn on RED

def error(message):
    print("ERROR : " + str(message))

def connect(message):
    print("CONNECTED")

def reconnect(message):
    print("RECONNECTED")

def disconnect(message):
    print("DISCONNECTED")

pubnub.subscribe(channel, callback=callback, error=callback,
                 connect=connect, reconnect=reconnect, disconnect=disconnect)