TCP connection to control servo motor - raspberry-pi

Question

I am writing a socket network application using android client and python server. The client side is almost perfect to send two values "1" and "2" . In the server side, the server will receive the value to check if the value equal to "1", the the motor servo will move from right to left or if the value equal to 2 the motor will move from left to right. Please look at the code:
# server.py
import socket
import RPi.GPIO as IO
import time
IO.setmode(IO.BOARD)
IO.setup(12,IO.OUT)
pwm2=IO.PWM(12,50)
# create a socket object
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# get local machine name
host = "192.168.1.10"
# bind to the port
s.bind((host, 18050))
# queue up to 5 requests
s.listen(1)
while True:
print("Listenng to the client" )
# establish a connection
clientsocket,addr = s.accept()
print("Got a connection from %s" % str(addr))
d=int(clientsocket.recv(1024))
if d==1:
print(d, "right to left")
pwm2.start(12)
time.sleep(3)
pwm2.stop()
elif d==2:
print(d, "left to right")
pwm2.start(2)
time.sleep(3)
pwm2.stop()
IO.cleanup()
s.close()
In the implementation, a strange behavior always happen. Sometimes the motors will move while at other times they are not. Moreover, they will move only one time from right to left and left to right. The result is as follow:
>>
Listenng to the client
Got a connection from ('192.168.1.9', 1313)
(1, 'right to left') # Movement occurs
Listenng to the client
Got a connection from ('192.168.1.9', 1337)
(2, 'left to right') # Movement occurs
Listenng to the client
Got a connection from ('192.168.1.9', 1383)
(1, 'right to left') # No Movement occurs
Listenng to the client
Got a connection from ('192.168.1.9', 1416)
(2, 'left to right') # No Movement occurs
Listenng to the client
Got a connection from ('192.168.1.9', 1445)
(1, 'right to left') # No Movement occurs
Listenng to the client
Got a connection from ('192.168.1.9', 1528)
(2, 'left to right') # No Movement occurs
Listenng to the client
Got a connection from ('192.168.1.9', 1574)
(1, 'right to left') # No Movement occurs
Listenng to the client
Please any suggestion ?... The whole idea is to control the servo by sending 1 or 2 from android activity. Thank you in advance for any help you may lend.

Answer 1

3 suggestions :
You should not accept connection in the loop. You had better accepting only once and then working with this connection as long as you need it.
If you dont mind your servo to be on between two calls to your service, maybe you could avoid starting/stopping the PWM pin and just change the duty (function ChangeDutyCycle(xx))
If you can use the GPIO18 (pin 12) as it is hardware PWM. The software ones works well but they use DMA transfer to achieve this which can be resource consuming (I experienced some delay too)