python_light_sensor.py

gistfile1.txt

import time, sys, math
from grove.adc import ADC

__all__ = ["GroveLightSensor"]

st = 1#sleep time


class GroveLightSensor(object):
    '''
    Grove Light Sensor class

    Args:
        pin(int): number of analog pin/channel the sensor connected.
    '''
    def __init__(self, channel):
        self.channel = channel
        self.adc = ADC()

    @property
    def light(self):
        '''
        Get the light strength value, maximum value is 100.0%

        Returns:
            (int): ratio, 0(0.0%) - 1000(100.0%)
        '''
        value = self.adc.read(self.channel)
        return value
    
    

Grove = GroveLightSensor




# detect unicode
one_byte_mask   = 0b00000000
two_byte_mask   = 0b11000000
three_byte_mask = 0b11100000
four_byte_mask  = 0b11110000

def used_four_byte(bin_byte):
    return (bin_byte & four_byte_mask) == four_byte_mask

def used_three_byte(bin_byte):
    return (bin_byte & three_byte_mask) == three_byte_mask

def used_two_byte(bin_byte):
    return (bin_byte & two_byte_mask) == two_byte_mask

def used_one_byte(bin_byte):
    return (bin_byte & one_byte_mask) == one_byte_mask

def detect_bytes_n(sensor, n):
    byte_arr = []
    for _ in range(0, n):
        one_byte = detect_one_byte(sensor)
        byte_arr.append(int(format(int(one_byte, 2), '08b'), 2))
    return byte_arr

def detect_bytes(sensor):
    byte_msg = ""
    byte_arr = []
    #print('Detecting light...')
    one_byte_str = detect_one_byte(sensor)
    one_byte = int(format(int(one_byte_str, 2), '08b'), 2)
    byte_arr.append(one_byte)

    if used_four_byte(one_byte):
        byte_arr.extend(detect_bytes_n(sensor, 3))
    elif used_three_byte(one_byte):
        byte_arr.extend(detect_bytes_n(sensor, 2))
    elif used_two_byte(one_byte):
        byte_arr.extend(detect_bytes_n(sensor, 1))
    elif used_one_byte(one_byte):
        pass

    # ascii
    if len(byte_arr) == 1 :
        return byte_decode(one_byte_str)
        # return ''.join(chr(b) for b in byte_arr)
    # unicode
    return bytearray(byte_arr).decode(encoding = 'utf-8')


def detect_one_byte(sensor):
    byte_msg = ""
    #print('Detecting light...')
    for _ in range(0,8) :
        
        if sensor.light >= 50:
            byte_msg += '1'
        else :
            byte_msg += '0'
        
        print('Light value: {0}'.format(sensor.light))
        time.sleep(st)
    
    return byte_msg
    # return byte_decode(byte_msg)
        
        
        
    


def byte_decode(byte_msg):
    
    #ord(A) == 65
    #chr(65) == 'A'
    # add bin format to string ex : 0b01000001 
    byte_msg = '0b' + byte_msg 
    c = int(byte_msg,2) # change string for binary  to int decimal
    return chr(c)
    
    
    
    

def detect_preamable(sensor):
    
    byte_msg = ""
    #print('Detecting light...')
    for _ in range(0,16) :
        
        if sensor.light >= 50:
            byte_msg += '1'
        else :
            byte_msg += '0'
        
        
        print('Light value: {0}'.format(sensor.light))
        time.sleep(st)
    
    
    if(byte_msg == '1010101010101010'):
        return True
    else:
        return False
    




def main():
    from grove.helper import SlotHelper
    sh = SlotHelper(SlotHelper.ADC)
    pin = sh.argv2pin()
    
    num =''
    msg = ''
    sensor = GroveLightSensor(pin)
    while sensor.light < 100:
        continue
    
    print('Ready')
    
    while not detect_preamable(sensor):
        print('Not preamable: ')
    
    
    # length of message
    for _ in range(0,2):
        num += (byte_decode(detect_one_byte(sensor)))
        
    for _ in range(0,int(num)):
        # msg += (detect_one_byte(sensor))
        msg += (detect_bytes(sensor))
    
    print('Your msg is: ' + msg)
        

if __name__ == '__main__':
    main()