How to run ESC Brushless Motor on raspberry Pi using Python?

Question

I am a very new to raspberry pi and hardware. I am trying to spin a brushless motor with ESC. below is the code (taken from a youtube video) that spins the motor till 9 and then slows it down till 4. but I want to run the motor without loops and without changing the duty cycles. Means when i run the program the motor should spin and when i stop the program the motor should stop spinning. Please update the below code.

Sorry for my bad English. I hope I am clear what I need.

Below is the code that I have taken from a video.

Code:

p = GPIO.PWM(7, 50)

p.start(0)
print ("starting 0")
time.sleep(3)

p.ChangeDutyCycle(3)
print("start")
time.sleep(5)



while True:
    i = 4
    while i<10:
        
        print(i)
        p.ChangeDutyCycle(i)
        time.sleep(.05)
        i +=.02
    
    while i>4:
        print(i)
        p.ChangeDutyCycle(i)
        time.sleep(.05)
        i -=.05

Answer 1

I am assuming the motor you want to control is a brushed DC motor and not a brushless, otherwise you would need a driver between the RPI and the motor. For a Brushed DC motor, you control the speed of the motor by changing the duty cycle of the PWM output. If you don't want to change the speed, simply set a dutycycle and stay with it. Check this example based on https://sourceforge.net/p/raspberry-gpio-python/wiki/PWM/:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BOARD)
GPIO.setup(7, GPIO.OUT)

p = GPIO.PWM(7, 50)
p.start(10)
input('Press return to stop:') 
p.stop()
GPIO.cleanup()

Here we are using GPIO 7 with a switching frequency of 50Hz and 10% of dutycycle. Adjust the values to suit your needs.