RoboRally/micropython_firmware/main.py

import machine
import sys
from machine import I2C, Pin

import d1motor

import time
import usocket
import esp

class Motor:
    def __init__(self, enable, dir1, dir2):
        self.enable_pin = machine.Pin(enable, machine.Pin.OUT)
        self.enable_pwm = machine.PWM(self.enable_pin)
        self.enable_pwm.freq(500)

        self.dir1_pin = machine.Pin(dir1, machine.Pin.OUT)
        self.dir2_pin = machine.Pin(dir2, machine.Pin.OUT)

        self.direction = 1 # default direction: dir1_pin = HIGH, dir2_pin = LOW
        self.reverse()

    def reverse(self):
        self.direction = not self.direction
        self.dir1_pin.value(self.direction)
        self.dir2_pin.value(not self.direction)

    def speed(self, value):
        if value > 0: # forward
            if not self.direction: # switch direction if necessary
                self.reverse()
        else: # backward
            if self.direction: # switch direction if necessary
                self.reverse()
        # apply value as pwm signal
        self.enable_pwm.duty(abs(value)*10)


class Robot:
    def __init__(self):
        i2c = False
        if i2c:
            print("setting up I2C ...")
            #d1 = Pin(5)
            #d2 = Pin(4)
            #i2c = I2C(scl=d1, sda=d2)
            #i2c_scan = i2c.scan()
            i2c_scan = []
            if len(i2c_scan) > 0:
                i2c_addr = i2c_scan[0]
                print("i2c scan = {}".format(i2c_addr))
                print("setting up motors ...")
                self.m1 = d1motor.Motor(0, i2c, address=i2c_addr)
                self.m2 = d1motor.Motor(1, i2c, address=i2c_addr)
                self.m1.speed(0)
                self.m2.speed(0)
                print("motor setup complete!")
            else:
                print("error: no i2c interfaces found!")
                sys.exit(1) 
        else:
            self.m1 = Motor(14, 13, 12)
            self.m2 = Motor(5, 0, 4)

        ip = my_ip[0]
        # setup socket for remote control 
        self.addr = usocket.getaddrinfo(ip, 1234)[0][-1]

    def remote_control(self):
        while True:
            print("setting up socket communication ...")
            socket_setup_complete = False
            while not socket_setup_complete:
                try:
                    print("trying to create socket on address {}".format(self.addr))
                    socket = usocket.socket()
                    socket.bind(self.addr)
                    print("socket setup complete!")
                    socket_setup_complete = True
                except Exception as e:
                    print("could not create socket. error msg: {}\nwaiting 1 sec and retrying...".format(e))
                    time.sleep(1.0)

            print("waiting for connections on {} ...".format(self.addr))
            socket.listen(1)
            res = socket.accept() # this blocks until someone connects to the socket
            comm_socket = res[0]
            print("connected!")
            listening = True
            try:
                while listening:
                     # expected data: '(t, u1, u2)'\n"
                     # where ui = control for motor i
                     # ui \in [-1.0, 1.0]
                         data = comm_socket.readline()
                         data_str = data.decode()
                         print("Data received: {}".format(data_str))
                         print("processing data = {}".format(data_str))
                         l = data_str.strip('()\n').split(',')
                         print("l = {}".format(l))
                         u1 = int(float(l[0])*100)
                         print("u1 = {}".format(u1))
                         u2 = int(float(l[1])*100)
                         print("u2 = {}".format(u2))
                         
                         self.m1.speed(u1)
                         self.m2.speed(u2)
            except ValueError:
                print("ValueError: Data has wrong format.")
                print("Data received: {}".format(data_str))
            except IndexError:
                print("IndexError: Data has wrong format.")
                print("Data received: {}".format(data_str))
            except Exception as e:
                print("Some other error occured")
                print("Exception: {}".format(e))
            finally:    
                print("Shutting down ...")
                u1 = u2 = 0
                self.m1.speed(u1)
                self.m2.speed(u2)
                listening = False
                comm_socket.close()
                socket.close()
                del comm_socket
                del socket

wall_e = Robot()
wall_e.remote_control()