server.py

import machine
import socket
import utime
import network
import rc
import time


steer_key=None
gear=1

do_steer=False
#steer_directio ,[0-127] steer right, [128-255] steer left
#speed_direction ,[0-127] going forward, [128-255] going backward
steering_step=30

steering_trim=124

always_exec_keys=['Key.up','Key.down','Key.left','Key.right']

state=[0,0] #[speed_value,steer_value,steer trim]
def get_next_steer():
  global steer_key,do_steer,state,gear,steering_step
  
  if state[1]<128:
    state[1]=state[1]+steering_step if state[1]+steering_step<128 else 127
  else:
    state[1]=state[1]+steering_step if state[1]+steering_step<256 else 255
 

def driver():

  global steer_key,do_steer,state,gear,steering_trim,always_exec_keys

  machine.freq(160000000)
  rc.setup()
  rc.bind()
 
  ap = network.WLAN(network.AP_IF) # create access-point interface
  ap.active(True)         # activate the interface
  ap.config(essid='ESP-carr') # set the ESSID of the access point

  
  UDP_IP = "0.0.0.0"
  UDP_PORT = 1327
  
  sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
  sock.bind((UDP_IP, UDP_PORT))
  sock.setblocking(0)  
  
  prev_data=None
  while True:

    #do v202 stuffs in loop
    rc.process(state[1],state[0],steering_trim)
    #if steer key pressed ,steering step by step
    if do_steer:
      get_next_steer()

    data=None
    try:
         
        data, addr = sock.recvfrom(1024)
        data=data.decode()
       
        if data not in always_exec_keys:
          if data==prev_data:
             continue
          else:
            prev_data=data
    except:
        pass
      
      
    if not data:
        
           continue
        
    
    key = data
    if key==steer_key:
      continue
    elif key == "'w'":
        state[0]=30*gear

    elif key == "'s'":
        state[0]=128+(30*gear)

    elif key == "'d'":
         steer_key='d' 
         state[1]=0
         do_steer=True
          
    elif key == "'a'":
         steer_key='a'
         state[1]=128
         do_steer=True

    elif key == "!'w'":
      state[0]=0
        
    elif key == "!'s'":
      state[0]=0
         
    elif key == "!'d'":
      if steer_key=='d':
        do_steer=False
        state[1]=0

    elif key == "!'a'":
      if steer_key=='a':
        do_steer=False
        state[1]=0
        
    elif key == "Key.up":

        if gear<4:
          gear+=1

          #to change gear in runtime
          if state[0]!=0:
            state[0]+=30
        

    elif key == "Key.down":
        if gear>1:
          gear-=1

          #to change gear in runtime
          if state[0]!=0:
            state[0]-=30
    elif key == "Key.left":

        if steering_trim>=10:

         steering_trim-=2
         

    elif key == "Key.right":

        if steering_trim<=245:
         steering_trim+=2