RE: MotorCape w/ uboot_overlay and Errors with Sysfs Entries/BBBW

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set_

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Feb 2, 2021, 8:20:30 AM2/2/21
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Hello,

I have just come across some issues:

  • What once worked does not work any longer
  • The source has changed a bit but I am receiving an error before the changes
  • I have some Python3 source and a server via Flask and HTML
I am giving this source below to better make you understand what is happening on my end of the spectrum. Oh and...for some reason, the source only allows for non-like numerical values.

uname -a >>> Linux beaglebone 4.19.94-ti-r58
cat /etc/dogtag >>> BeagleBoard.org Debian Buster IoT Image 2020-04-06
...

For the uboot_overlay, here is the command to look it over w/ my overlay:

cat /boot/uEnv.txt >>> ###Overide capes with eeprom
uboot_overlay_addr0=/lib/firmware/BBORG_MOTOR-00A2.dtbo

oh and the source:

    #!/usr/bin/python3

    from flask import Flask, render_template
    import Adafruit_BBIO.GPIO as GPIO
    import Adafruit_BBIO.PWM as PWM
    from time import sleep

    class Motor:
        def __init__(self, dir_pin, pwm_pin, pwm_freq):
            self.dir_pin = dir_pin
            self.pwm_pin = pwm_pin
            self.value = 0

            PWM.start(pwm_pin, 0, pwm_freq)
            GPIO.setup(dir_pin, GPIO.OUT)

        def set(self, value):
            if value == self.value:
                return

            assert -100 <= value <= 100

            if (value < 0) != (self.value < 0):
                # changing direction
                PWM.set_duty_cycle(self.pwm_pin, 0)
                GPIO.output(self.dir_pin, value < 0)

            PWM.set_duty_cycle(self.pwm_pin, abs(value))
            self.value = value

    motor1 = Motor(dir_pin="P8_18", pwm_pin="P9_16", pwm_freq=1000)
    motor2 = Motor(dir_pin="P8_16", pwm_pin="P9_14", pwm_freq=1000)
    motor3 = Motor(dir_pin="P8_14", pwm_pin="P8_13", pwm_freq=1000)
    motor4 = Motor(dir_pin="P8_26", pwm_pin="P8_19", pwm_freq=1000)

    def set_motorOne(v1):
        motor1.set(v1)

    def set_motorTwo(v2):
        motor2.set(v2)

    def set_motorThree(v3):
        motor3.set(v3)

    def set_motorFour(v4):
        motor4.set(v4)

    app = Flask(__name__)

    @app.route("/")
    def homepage(title="homepage"):
        return render_template("BootGoOne.html", title=title)

    def add_motors_routeOne(state, v1):
        @app.route("/" + state, endpoint=state)
        def handlerOne():
            set_motorOne(v1)
            if add_motors_routeOne == 0:
                PWM.stop("P9_16")
            else:
                pass

            return homepage(title=state)

    add_motors_routeOne("0",   0)
    add_motors_routeOne('40', 40)
    add_motors_routeOne('50', 50)
    add_motors_routeOne('60', 60)
    add_motors_routeOne('70', 70)
    add_motors_routeOne('80', 80)
    add_motors_routeOne('90', 90)
    add_motors_routeOne('100', 100)

Okay...so:

  • When I add another 'add_motors_routeOne' as a separate call under another motor, I get some odd behavior.
    • For instance, 'add_motors_routeTwo', would begin to make issues with calling 'add_motors_routeTwo("0", 0) at the value 0. 
Anyway...the issue is that it begins to be a sysfs issue or an assertion error on my part.

    Traceback (most recent call last):
      File "Moto/motocape/MotorCapeOne/MotorCapeTwo.py", line 92, in <module>
        add_motors_routeTwo("0",   0)
      File "Moto/motocape/MotorCapeOne/MotorCapeTwo.py", line 83, in     add_motors_routeTwo
        @app.route("/" + state, endpoint=state)
      File "/usr/lib/python3/dist-packages/flask/app.py", line 1250, in decorator
        self.add_url_rule(rule, endpoint, f, **options)
      File "/usr/lib/python3/dist-packages/flask/app.py", line 66, in wrapper_func
        return f(self, *args, **kwargs)
      File "/usr/lib/python3/dist-packages/flask/app.py", line 1221, in add_url_rule
        'existing endpoint function: %s' % endpoint)
    AssertionError: View function mapping is overwriting an existing endpoint function: 0

Above is where you can find my error with the current config. of the python3 source from above.

Seth

evilwulfie

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Feb 2, 2021, 8:32:08 AM2/2/21
to beagl...@googlegroups.com
On 2/2/2021 6:20 AM, set_ wrote:
Hello,

I have just come across some issues:

  • What once worked does not work any longer
What did you do between it working and it not working ?


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set_

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Feb 2, 2021, 8:15:43 PM2/2/21
to BeagleBoard
Hello,

Well...when I say working, I mean remedially working. Sysfs did return errors and I was always receiving the error about multiple values that are exactly the same.

I basically changed the source to handle four motors, added a server, and managed to adopt a "kill switch" in source via the Adafruit_BBIO.PWM functions and Adafruit_BBIO.GPIO functions.

Seth

P.S. One of the four motors seems nice but when I am making a quadruped, four motors are needed so far. Anyway, do you see an issue w/ the source as it may be as of now?

set_

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Feb 2, 2021, 8:26:28 PM2/2/21
to BeagleBoard
Oh and Hello Again,

I forgot to mention the major change. 

So, instead of each motor handling its own PWM frequency in source along w/ duty_cycle, I had previously a method that handled one value that all motors were being controlled.

For instance:
  • The above source handles, what I thought would be, one motor and the peripherals of pwm and gpio.
  • The below source is what worked w/out the addition of three motors, separate values per motor, and no "failsafe."
    def set_motors(v1, v2, v3, v4):
        motor1.set(v1)
        motor2.set(v2)
        motor3.set(v3)
        motor4.set(v4)

     app = Flask(__name__)

    @app.route("/")
    def homepage(title="homepage"):
        return render_template("BootGoOne.html", title=title)

    def add_motors_route(state, v1, v2, v3, v4):
        @app.route("/" + state, endpoint=state)
        def handlerOne():
            set_motors(v1, v2, v3, v4)
            # if add_motors_routeOne == 0:
                # PWM.stop("P9_16")
            else:
                pass

            return homepage(title=state)

    add_motors_route('0',       0)
    add_motors_route('25',  25)

    and etc...

That is all. 

Seth

set_

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Feb 4, 2021, 10:12:40 PM2/4/21
to BeagleBoard
Hello,

Do not worry about it. I made some random class function and the whole set up is in working order (remedial anyhow)...

Seth

P.S. BBBW still in the working ranks!

On Tuesday, February 2, 2021 at 7:32:08 AM UTC-6 evilw...@gmail.com wrote:
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