Problem with the method ping()

[arielkantorovich]

Hi,
I want to read PWM Signal, My hardware is Arduino Mega and I use PyFirmata Library because my code run in python.
When I use pin8.ping() i except error.
The ping() Method really work?
I would happy to any help thanks.

My code:
from pyfirmata import ArduinoMega, util
import threading
import time

def trans_pwm(pin):
while True:
x = int(input("Please enter angle for Servo: "))
angle = int(100 / 90 * x + 45)
pin.write(angle)

def receiv_pwm(pin):
while True:
print("Pulse Time= ", pin.ping(), " [Sec]")
time.sleep(0.0002)

try:
# Initialize Hardware Configuration
board = ArduinoMega('COM8')
it = util.Iterator(board)
it.start()

# set up pin D2 as Servo Output
pin2 = board.get_pin('d:2:s')
# set up pin D8 as PWM Input
pin8 = board.get_pin('d:8:o')
pin8.ping()

# Use Threading to Transmit and receive in the same time
t1 = threading.Thread(target=trans_pwm, args=(pin2,))
t2 = threading.Thread(target=receiv_pwm, args=(pin8,))
t1.start()
t2.start()
t1.join()
t2.join()

except:
print("error")

finally:
board.exit()