RevPi ModIO2 and OOP

[wmatte]

Hello everybody,

I am happy to take part into this forum using this amazing product

I am managing an industrial physical simulator with a bunch of sensors and actuators.
I would like to set up my code following OOP principles, with a class structure that reflects the actual real world.

BTW, I am having some issues, since looks like the RevPi I am using does not digest very well my idea.

In the following my setup:
- RevPi Core S
- RevPi DIO module.

In the following I report a test code that I am using:

The first class is called TestCycle. It contains the revpi cycle loop.

Code: Select all

import revpimodio2
from saw import Saw

class TestCycle():
    """Testing over the RevPi OOP functionalities."""
    def __init__(self):
        # Instantiate RevPiModIO controlling library
        self.rpi = revpimodio2.RevPiModIO(autorefresh=True)
        # Handle SIGINT / SIGTERM to exit program cleanly
        self.rpi.handlesignalend(self.cleanup_revpi)
        
        # Saw process time counter
        self.time_sens_saw_count = 0

        # Instantiating all the needed objects
        self.saw = Saw()
        

    def cleanup_revpi(self):
        """Cleanup function to leave the RevPi in a defined state."""
        # Switch of LED and outputs before exit program
        self.rpi.core.a1green.value = False
        # Support time sensors
        self.time_sens_saw_count = 0
          
    def write(self):
        """Writes the output actuators states"""
        # Assigning to a the relative sensor, the variable value
        # Saw - Motor activation
        #self.rpi.io['O_4'].value = self.act_saw
        

    def start(self):
        """Start event system and own cyclic loop."""
        print('start')
        # Start event system loop without blocking here. Reference at 
        # https://revpimodio.org/en/events-in-the-mainloop/
        self.rpi.mainloop(blocking=False)

        while (self.rpi.exitsignal.wait(0.05) == False):
            # Sets the Rpi a1 light: switch on / off green part of LED A1 | or 
            # do other things
            self.rpi.core.a1green.value = not self.rpi.core.a1green.value

            # 2. Makes something
            if (self.time_sens_saw_count < 30):
                self.saw.turn_on()
                self.time_sens_saw_count += 1
            elif (self.time_sens_saw_count >= 30 and 
                  self.time_sens_saw_count < 60):
                self.saw.turn_off()
                self.time_sens_saw_count += 1
            elif (self.time_sens_saw_count >= 60):
                self.time_sens_saw_count = 0

if __name__ == "__main__":
    # Instantiating the controlling class
    root = TestCycle()
    # Launch the start function of the RevPi event control system
    root.start()

The second class is the one imported in the TestCycle __init__. In the following, the code:

Code: Select all

import revpimodio2

class Saw(object):
    """Saw class for saw objects."""
    def __init__(self):
        # Instantiate RevPiModIO controlling library
        self.rpi = revpimodio2.RevPiModIO(autorefresh=True)
    
    def turn_on(self):
        self.rpi.io['O_4'].value = True

    def turn_off(self):
        self.rpi.io['O_4'].value = False

Well, I would really like to be able to control actuators and look for sensors from inside objects, using associated classes, like I did in the Saw() class.
Btw, it seems not completely possible: doing so, the actuator voltage does not stay steadily at 24V, but instead floats between 15 and 23.something Volts.

What I am doing wrong?
How can I achieve my target?

Thank you in advance for the support of the community!

[RevPiModIO]

Hi

On the Revolution Pi should be only one instance of RevPiModIO. So you just have to pass your instance to the other classes and your program should work

By that method you can write control classes independently of the instantiation of the RevPiModIO module. The control classes will work alway, doesn't matter if you pass a RevPiModIO or RevPiNetIO instance.

Code: Select all

import revpimodio2
from saw import Saw

class TestCycle():
    """Testing over the RevPi OOP functionalities."""
    def __init__(self):
        # Instantiate RevPiModIO controlling library
        self.rpi = revpimodio2.RevPiModIO(autorefresh=True)
        # Handle SIGINT / SIGTERM to exit program cleanly
        self.rpi.handlesignalend(self.cleanup_revpi)
        
        # Saw process time counter
        self.time_sens_saw_count = 0

        # Instantiating all the needed objects
        self.saw = Saw(self.rpi)
        

    def cleanup_revpi(self):
        """Cleanup function to leave the RevPi in a defined state."""
        # Switch of LED and outputs before exit program
        self.rpi.core.a1green.value = False
        # Support time sensors
        self.time_sens_saw_count = 0
          
    def write(self):
        """Writes the output actuators states"""
        # Assigning to a the relative sensor, the variable value
        # Saw - Motor activation
        #self.rpi.io['O_4'].value = self.act_saw
        

    def start(self):
        """Start event system and own cyclic loop."""
        print('start')
        # Start event system loop without blocking here. Reference at 
        # https://revpimodio.org/en/events-in-the-mainloop/
        self.rpi.mainloop(blocking=False)

        while (self.rpi.exitsignal.wait(0.05) == False):
            # Sets the Rpi a1 light: switch on / off green part of LED A1 | or 
            # do other things
            self.rpi.core.a1green.value = not self.rpi.core.a1green.value

            # 2. Makes something
            if (self.time_sens_saw_count < 30):
                self.saw.turn_on()
                self.time_sens_saw_count += 1
            elif (self.time_sens_saw_count >= 30 and 
                  self.time_sens_saw_count < 60):
                self.saw.turn_off()
                self.time_sens_saw_count += 1
            elif (self.time_sens_saw_count >= 60):
                self.time_sens_saw_count = 0

if __name__ == "__main__":
    # Instantiating the controlling class
    root = TestCycle()
    # Launch the start function of the RevPi event control system
    root.start()

----

Code: Select all

class Saw(object):
    """Saw class for saw objects."""
    def __init__(self, rpi):
        # take already existing instance of RevPiModIO controlling library
        self.rpi = rpi
    
    def turn_on(self):
        self.rpi.io['O_4'].value = True

    def turn_off(self):
        self.rpi.io['O_4'].value = False

Sven

[wmatte]

Hi

On the Revolution Pi should be only one instance of RevPiModIO. So you just have to pass your instance to the other classes and your program should work

By that method you can write control classes independently of the instantiation of the RevPiModIO module. The control classes will work alway, doesn't matter if you pass a RevPiModIO or RevPiNetIO instance.

Code: Select all

import revpimodio2
from saw import Saw

class TestCycle():
    """Testing over the RevPi OOP functionalities."""
    def __init__(self):
        # Instantiate RevPiModIO controlling library
        self.rpi = revpimodio2.RevPiModIO(autorefresh=True)
        # Handle SIGINT / SIGTERM to exit program cleanly
        self.rpi.handlesignalend(self.cleanup_revpi)
        
        # Saw process time counter
        self.time_sens_saw_count = 0

        # Instantiating all the needed objects
        self.saw = Saw(self.rpi)
        

    def cleanup_revpi(self):
        """Cleanup function to leave the RevPi in a defined state."""
        # Switch of LED and outputs before exit program
        self.rpi.core.a1green.value = False
        # Support time sensors
        self.time_sens_saw_count = 0
          
    def write(self):
        """Writes the output actuators states"""
        # Assigning to a the relative sensor, the variable value
        # Saw - Motor activation
        #self.rpi.io['O_4'].value = self.act_saw
        

    def start(self):
        """Start event system and own cyclic loop."""
        print('start')
        # Start event system loop without blocking here. Reference at 
        # https://revpimodio.org/en/events-in-the-mainloop/
        self.rpi.mainloop(blocking=False)

        while (self.rpi.exitsignal.wait(0.05) == False):
            # Sets the Rpi a1 light: switch on / off green part of LED A1 | or 
            # do other things
            self.rpi.core.a1green.value = not self.rpi.core.a1green.value

            # 2. Makes something
            if (self.time_sens_saw_count < 30):
                self.saw.turn_on()
                self.time_sens_saw_count += 1
            elif (self.time_sens_saw_count >= 30 and 
                  self.time_sens_saw_count < 60):
                self.saw.turn_off()
                self.time_sens_saw_count += 1
            elif (self.time_sens_saw_count >= 60):
                self.time_sens_saw_count = 0

if __name__ == "__main__":
    # Instantiating the controlling class
    root = TestCycle()
    # Launch the start function of the RevPi event control system
    root.start()

----

Code: Select all

class Saw(object):
    """Saw class for saw objects."""
    def __init__(self, rpi):
        # take already existing instance of RevPiModIO controlling library
        self.rpi = rpi
    
    def turn_on(self):
        self.rpi.io['O_4'].value = True

    def turn_off(self):
        self.rpi.io['O_4'].value = False

Sven

Thank you vey much for your help!
I tried the suggested solution: of course it work, and (more important) I fully understood the meaning of it!

I will report if I will have further issues in the next days or if I accomplished the project as expected!