035 - MicroPython TechNotes: Dual Motor Driver

  1# More details can be found in TechToTinker.blogspot.com 
  2# George Bantique | tech.to.tinker@gmail.com
  3
  4from machine import Pin
  5from machine import PWM
  6
  7# Create pin assignment instance
  8AIN1 = Pin(12, Pin.OUT)
  9PWMA = Pin(13, Pin.OUT)
 10AIN2 = Pin(14, Pin.OUT)
 11BIN1 = Pin(26, Pin.OUT)
 12PWMB = Pin(27, Pin.OUT)
 13BIN2 = Pin(32, Pin.OUT)
 14pwmA = PWM(PWMA) # attached PWM driver to GPIO pin
 15pwmB = PWM(PWMB)
 16pwmA.freq(500)   # sets default frequency
 17pwmB.freq(500)
 18pwmA.duty(0)     # initialized the PWM pulse to OFF
 19pwmB.duty(0)
 20
 21# A function for stopping the motors using digital logic
 22# A logic 0 turns OFF the pin
 23# A logic 1 turns ON the pin
 24def dig_move_stop():
 25    PWMA.value(0)
 26    AIN1.value(0)
 27    AIN2.value(0)
 28    PWMB.value(0)
 29    BIN1.value(0)
 30    BIN2.value(0)
 31    print('[dig] Moving stopped.')
 32
 33# A function for moving forward using digital logic
 34# PWMx pin:
 35#    logic 1 - will enable the motor
 36#    logic 0 - disable the motor
 37# AIN1 and AIN2 or (BIN1 and BIN2) pins:
 38#    * this pins should not be driven both logic 1
 39#    ** AIN1 = 0 and AIN2 = 1 will rotate the motor forward
 40#    ** BIN1 = 0 and BIN2 = 1 will rotate the motor forward
 41def dig_move_forward():
 42    pwmA.duty(1023)
 43    AIN1.value(0)
 44    AIN2.value(1)
 45    pwmB.duty(1023)
 46    BIN1.value(0)
 47    BIN2.value(1)
 48    print('[dig] Moving forward.')
 49
 50# A function for moving backward using digital logic
 51# The logic here is just the opossite of dig_move_forward()
 52def dig_move_backward():
 53    pwmA.duty(1023)
 54    AIN1.value(1)
 55    AIN2.value(0)
 56    pwmB.duty(1023)
 57    BIN1.value(0)
 58    BIN2.value(1)
 59    print('[dig] Moving backward.')
 60
 61# A function to demonstrate stopping the motor using pwm
 62# A PWM duty value of 0 will disable the motor driver
 63# A PWM duty value of 1 to 1023 will control the speed
 64#   of rotation of the motor
 65def pwm_move_stop():
 66    pwmA.duty(0)
 67    AIN1.value(0)
 68    AIN2.value(0)
 69    pwmB.duty(0)
 70    BIN1.value(0)
 71    BIN2.value(0)
 72    print('[pwm] Moving stopped.')
 73
 74# A function to demonstrate moving forward with controlled speed
 75# A PWM duty value can be set both for motor A and B with value
 76#   from 0 to 1023.
 77# A PWM duty value for both motor A and B is default to 700 incase
 78#   you don't want to input in function parameters
 79def pwm_move_forward(pwm=700):
 80    pwmA.duty(pwm)
 81    AIN1.value(0)
 82    AIN2.value(1)
 83    pwmB.duty(pwm)
 84    BIN1.value(0)
 85    BIN2.value(1)
 86    print('[pwm] Moving forward.')
 87
 88# A function to demonstrate moving backward with controlled speed
 89# The logic here works the same as pwm_move_forward()
 90def pwm_move_backward(pwm=700):
 91    pwmA.duty(pwm)
 92    AIN1.value(1)
 93    AIN2.value(0)
 94    pwmB.duty(pwm)
 95    BIN1.value(0)
 96    BIN2.value(1)
 97    print('[pwm] Moving backward.')
 98    
 99    
100# The following can be tested using the REPL:
101# 1. To move the toy car forward:
102# dig_move_forward()
103# 2. To move the toy car backward:
104# dig_move_backward()
105# 3. To stop the car:
106# dig_move_stop()
107# ***********************************************************
108# Or you may also use the PWM in controlling the motor speed.
109# -----------------------------------------------------------
110# 4. To move the toy car foward with controlled speed:
111# pwm_move_forward()
112# 5. or you may set the speed of the motor:
113# pwm_move_forward(400)
114# 6. To move the toy car backward with controlled speed:
115# pwm_move_backward()
116# 7. or you may set the speed of the motor:
117# pwm_move_backward(500)
118# 8. And to pwm stop the toy car:
119# pwm_move_stop()

  1# More details can be found in TechToTinker.blogspot.com 
  2# George Bantique | tech.to.tinker@gmail.com
  3
  4from machine import Pin
  5from machine import PWM
  6from machine import ADC
  7from time import ticks_us
  8from time import sleep_ms
  9
 10def map(x, in_min, in_max, out_min, out_max): 
 11    return int((x - in_min) * (out_max - out_min) /
 12               (in_max - in_min) + out_min)
 13
 14AIN1 = Pin(12, Pin.OUT, Pin.PULL_DOWN, value=0)
 15PWMA = PWM(Pin(13, Pin.OUT, Pin.PULL_DOWN, value=0))
 16AIN2 = Pin(14, Pin.OUT, Pin.PULL_DOWN, value=0)
 17BIN1 = Pin(26, Pin.OUT, Pin.PULL_DOWN, value=0)
 18PWMB = PWM(Pin(27, Pin.OUT, Pin.PULL_DOWN, value=0))
 19BIN2 = Pin(32, Pin.OUT, Pin.PULL_DOWN, value=0)
 20
 21PWMA.freq(5000)
 22PWMA.duty(0)
 23PWMB.freq(5000)
 24PWMB.duty(0)
 25
 26led = Pin(2, Pin.OUT)
 27joy_x = ADC(Pin(33, Pin.IN))
 28joy_y = ADC(Pin(34, Pin.IN))
 29joy_x.atten(ADC.ATTN_11DB)
 30joy_y.atten(ADC.ATTN_11DB)
 31
 32def backward():
 33    AIN1.on()
 34    AIN2.off()
 35    BIN1.on()
 36    BIN2.off()        
 37
 38def forward():
 39    AIN1.off()
 40    AIN2.on()
 41    BIN1.off()
 42    BIN2.on()
 43
 44def stop():
 45#     PWMA.off()
 46#     PWMB.off()
 47    PWMA.duty(0)
 48    PWMB.duty(0)
 49
 50
 51start_A = ticks_us()
 52start_B = ticks_us()
 53interval_A = 0
 54interval_B = 0
 55signal_A = 0
 56signal_B = 0
 57
 58left_val = 0
 59right_val = 0
 60front_val = 0
 61back_val = 0
 62left_duty = 0
 63right_duty = 0
 64
 65while True:
 66    sleep_ms(100)
 67    
 68    # ******************************************************
 69    # Process the Joystick:
 70    # 1. Read the x and y analog values
 71    # 2. Convert it to directional values: L, R, F, B
 72    # ------------------------------------------------------
 73    x_val = joy_x.read()
 74    if x_val < 1875:
 75        # move left
 76        left_val = map(x_val,1874,0,0,1000)
 77        right_val = 0
 78    elif x_val > 1902:
 79        # move right
 80        right_val = map(x_val,1903,4095,0,1000)
 81        left_val = 0
 82    else:
 83        # move center
 84        left_val = 0
 85        right_val = 0
 86    y_val = joy_y.read()
 87    if y_val < 1917:
 88        # move backward
 89        back_val = map(y_val, 1916, 0, 0, 1000)
 90        front_val = 0
 91    elif y_val > 1944:
 92        # move forward
 93        front_val = map(y_val, 1945, 4095, 0, 1000)
 94        back_val = 0
 95    else:
 96        # stop moving
 97        front_val = 0
 98        back_val = 0
 99        
100    if front_val==0 and left_val==0 and right_val==0 and back_val==0: # A
101        # stop moving
102        left_duty = 0
103        right_duty = 0        
104    elif front_val!=0 and left_val==0 and right_val==0 and back_val==0: # B
105        forward()
106        left_duty = front_val
107        right_duty = front_val
108    elif front_val!=0 and left_val==0 and right_val!=0 and back_val==0: # C
109        forward()
110        left_duty = right_val 
111        right_duty = right_val * 8 // 10
112    elif front_val==0 and left_val==0 and right_val!=0 and back_val==0: # D
113        left_duty = 800 #right_val // 3 # rotates the left wheel
114        right_duty = 0
115    elif front_val==0 and left_val==0 and right_val!=0 and back_val!=0: # E
116        backward()
117        left_duty = right_val * 8 // 10
118        right_duty = right_val
119    elif front_val==0 and left_val==0 and right_val==0 and back_val!=0: # F
120        backward()
121        left_duty = back_val
122        right_duty = back_val
123    elif front_val==0 and left_val!=0 and right_val==0 and back_val!=0: # G
124        backward()
125        right_duty = left_val
126        left_duty = left_val * 8 // 10
127    elif front_val==0 and left_val!=0 and right_val==0 and back_val==0: # H
128        right_duty = 800 #left_val // 3 # rotates the right wheel
129        left_duty = 0
130    elif front_val!=0 and left_val!=0 and right_val==0 and back_val==0: # I
131        forward()
132        left_duty = left_val * 8 // 10
133        right_duty = left_val
134    else: # stop
135        left_duty = 0
136        right_duty = 0
137        
138    PWMA.duty(right_duty)
139    PWMB.duty(left_duty)
140    
141    print(left_val, right_val, front_val, back_val, left_duty, right_duty)