Figaro CDM7160 continuous I2C read w/busy PIN (Python)

gistfile1.txt

#!/usr/bin/env python
from smbus2 import SMBus, SMBusWrapper, i2c_msg
import time
import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BCM)
INPUT_PIN = 8  #The BUSY pin.
GPIO.setup(INPUT_PIN, GPIO.IN)

def inputLow(channel):

    with SMBusWrapper(1) as bus:
        #set the device to continuous read
        bus.write_byte(0x69, 0x1, 0x6)
        #read back 0x1
        byte1 = bus.read_byte(0x69,0)
        #read 0x2
        status = bus.read_byte(0x69,0)
        #read 0x3
        low_byte = bus.read_byte(0x69,0)
        #read 0x4
        high_byte = bus.read_byte(0x69,0)
        reading = (high_byte * 256) + low_byte
        print("c02 reading: " + str(reading))

def read_loop():
    while True:
        time.sleep(1)

if __name__ == "__main__":
    #set inputLow to fire when the busy pin drops to low.
    GPIO.add_event_detect(INPUT_PIN, GPIO.FALLING, callback=inputLow, bouncetime=200)
    read_loop()