Example Python code that use MediaTek Cloud Sandbox to control on-board Wi-Fi LED of LinkIt Smart 7688

mcs_blink.py

import requests
import socket
import threading
import logging
import mraa

# change this to the values from MCS web console
DEVICE_INFO = {
    'device_id' : 'YOUR_DEVICE_ID',
    'device_key' : 'YOUR_DEVICE_KEY'
}

# change 'INFO' to 'WARNING' to filter info messages
logging.basicConfig(level='INFO')

heartBeatTask = None

def establishCommandChannel():
    # Query command server's IP & port
    connectionAPI = 'https://api.mediatek.com/mcs/v2/devices/%(device_id)s/connections.csv'
    r = requests.get(connectionAPI % DEVICE_INFO, 
                 headers = {'deviceKey' : DEVICE_INFO['device_key'],
                            'Content-Type' : 'text/csv'})
    logging.info("Command Channel IP,port=" + r.text)
    (ip, port) = r.text.split(',')

    # Connect to command server
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((ip, int(port)))
    s.settimeout(None)
    
    # Heartbeat for command server to keep the channel alive
    def sendHeartBeat(commandChannel):
        keepAliveMessage = '%(device_id)s,%(device_key)s,0' % DEVICE_INFO
        commandChannel.sendall(keepAliveMessage)
        logging.info("beat:%s" % keepAliveMessage)

    def heartBeat(commandChannel):
        sendHeartBeat(commandChannel)
        # Re-start the timer periodically
        global heartBeatTask
        heartBeatTask = threading.Timer(40, heartBeat, [commandChannel]).start()
    
    heartBeat(s)
    return s

def waitAndExecuteCommand(commandChannel):
    while True:
        command = commandChannel.recv(1024)
        logging.info("recv:" + command)
        # command can be a response of heart beat or an update of the LED_control,
        # so we split by ',' and drop device id and device key and check length
        fields = command.split(',')[2:]

        if len(fields) > 1:
            timeStamp, dataChannelId, commandString = fields
            if dataChannelId == 'LED_control':
                # check the value - it's either 0 or 1
                commandValue = int(commandString)
                logging.info("led :%d" % commandValue)
                setLED(commandValue)

pin = None
def setupLED():
    global pin
    # on LinkIt Smart 7699, pin 44 is the Wi-Fi LED.
    pin = mraa.Gpio(44)
    pin.dir(mraa.DIR_OUT)

def setLED(state):
    # Note the LED is "reversed" to the pin's GPIO status.
    # So we reverse it here.
    if state:
        pin.write(0)
    else:
        pin.write(1)

if __name__ == '__main__':
    setupLED()
    channel = establishCommandChannel()
    waitAndExecuteCommand(channel)