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by moderatelyfunky
Tue Feb 26, 2019 12:27 am
Forum: Official Foundation Display
Topic: Official 7' touchscreen, rotate touch
Replies: 23
Views: 9491

Re: Official 7' touchscreen, rotate touch

Thanks, eatmyvolts. Your version worked!
by moderatelyfunky
Thu Sep 20, 2018 11:08 pm
Forum: Python
Topic: abort pigpiod wave_chain?
Replies: 3
Views: 474

Re: abort pigpiod wave_chain?

I am getting some unexpected behavior with my motors not running to their destinations using wave_chains. It's an odd symptom. The motors are woken up and the code shows print messages as expected, but the motors act like their step pins aren't set high. When I run the motors with PWM, the limit swi...
by moderatelyfunky
Thu Sep 20, 2018 12:35 pm
Forum: Python
Topic: abort pigpiod wave_chain?
Replies: 3
Views: 474

Re: abort pigpiod wave_chain?

I should have just tried it. Thanks, Joan!
by moderatelyfunky
Wed Sep 19, 2018 10:34 pm
Forum: Python
Topic: abort pigpiod wave_chain?
Replies: 3
Views: 474

abort pigpiod wave_chain?

I've added some limit switches to my stepper project and if they are reached before the wave_chain is completed, I'd like to cancel the chain. I saw wave_tx_stop(), but that is built for wave_send_repeat.

Is there a way to interrupt and cancel the remainder of a wave_chain?

Thanks for any ideas
by moderatelyfunky
Tue Sep 11, 2018 7:58 pm
Forum: Python
Topic: Quadrature encoder serial pins question
Replies: 11
Views: 654

Re: Quadrature encoder serial pins question

I'm considering replacing the steppers in my project with dc and I wasn't sure where to start, but now I know.

Thanks Outofhebots, I really appreciate both of these videos!
by moderatelyfunky
Wed Aug 29, 2018 12:01 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

Re: pigpio callbacks

@PiGraham, I appreciate all the time you've taken to help. I feel like I'm missing something fundamental, or maybe my attempt at describing the needs of this gadget for two modes of control was not clear. You say that You have the step count when you build the wave. No, in the mode where a user is c...
by moderatelyfunky
Tue Aug 28, 2018 7:21 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

Re: pigpio callbacks

I am using pigpio waves and wave_chains for moving from some current location to a previously saved, preset location and I was keeping track of those pulses. I still am, but it doesn't look like there's a need for them anymore. The reason I investigated pigpio callbacks is because I couldn't find a ...
by moderatelyfunky
Tue Aug 28, 2018 5:47 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

Re: pigpio callbacks

The information about homing sounds good, thanks. You can then provide pulses to move the motor and you just have to keep track of how many pulses you send to the driver, which is a quantity managed in your code so you don't need to count it from gpio pin callbacks. This is the part I'm confused abo...
by moderatelyfunky
Tue Aug 28, 2018 4:01 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

Re: pigpio callbacks

I'm just learning as I go, so I'd welcome any suggestions. What do you think is the best way to accomplish the goal of allowing a user to infinitely position a nut along a motor-driven lead screw where they want with a button press to start motion and another button to stop motion?
by moderatelyfunky
Tue Aug 28, 2018 2:56 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

Re: pigpio callbacks

@PiGraham, I'm using polulu drv8825 drivers with some generic bipolar steppers @Joan -Thanks for the confirmation, I don't think I'll exceed 2.5 kHz so it sounds like there's lots of headroom. I'm starting to get to know your library and I'm loving it. Thank you for your incredible skills and genero...
by moderatelyfunky
Tue Aug 28, 2018 1:54 pm
Forum: Python
Topic: Simple tkinter and Python3 help
Replies: 7
Views: 721

Re: Simple tkinter and Python3 help

I am working through the stepper learning process too, so take whatever I say with a grain of salt. Check out Joan's incredible pigpiod library - http://abyz.me.uk/rpi/pigpio/python.html . If you're looking for one speed all the time, there is PWM and the set_PWM_frequency method. pi.set_PWM_dutycyc...
by moderatelyfunky
Tue Aug 28, 2018 12:40 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

Re: pigpio callbacks

I think part of the problem is that I'm mixing my terms. When I say steps, I just mean a count of something that I can use to be set to zero for home and be added to / subtracted from with PWM or waves so I can be aware of the postion. I have two modes of operation, the first is pressing a button to...
by moderatelyfunky
Mon Aug 27, 2018 10:02 pm
Forum: Python
Topic: pigpio callbacks
Replies: 16
Views: 1402

pigpio callbacks

I am trying to keep track of steps my motors are taking.. In one method, I'm using PWM with a callback that increments/decrements a counter every time it's called for either edge. In another method, I'm updating the same counter based on the direction and number of pulse elements in the array I'm us...
by moderatelyfunky
Thu Aug 23, 2018 3:55 pm
Forum: Python
Topic: Syntax error
Replies: 2
Views: 354

Re: Syntax error

I think you'll need commas between the elements in your dicts
by moderatelyfunky
Thu Aug 23, 2018 12:40 pm
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

Re: pigpio - run stepper many steps precisely

Thanks again, Pootle. It's definitely more magic than I'm used to seeing. :)
bitMaskMagic.JPG
bitMaskMagic.JPG (39.06 KiB) Viewed 1290 times
by moderatelyfunky
Thu Aug 23, 2018 1:24 am
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

Re: pigpio - run stepper many steps precisely

Thanks pootle. Would you be willing to give me a couple of translation examples? I don't understand how to store them as integers. My project will need to set one to four pins.

(1<<21)

(1<<19) | (1<<17)

(1<<23) | (1<<17) | (1<<19)

(1<<19) | (1<<23) | (1<<17) | (1<<21)
by moderatelyfunky
Wed Aug 22, 2018 8:57 pm
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

Re: pigpio - run stepper many steps precisely

Following Joan's discussion here - https://www.raspberrypi.org/forums/viewtopic.php?p=717571#p717571 For most uses you are only concerned with one gpio. That is why the examples invariably only show one gpio. You can switch on and switch off any of gpios 0 - 31 with each pulse. You select the gpios ...
by moderatelyfunky
Wed Aug 22, 2018 4:39 pm
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

Re: pigpio - run stepper many steps precisely

Having each motor let a method know when it should be included in or excluded from an ongoing series of waves is a really neat idea. I think it would eliminate a particular problem I’m working through now, which is to dynamically build the pulse for only the pins that need it. In my scenario, as all...
by moderatelyfunky
Tue Aug 21, 2018 12:37 pm
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

Re: pigpio - run stepper many steps precisely

I have some details to work out about managing four steppers at once with different step counts, but it seems possible now with wave_chaining. The looping design within it is just amazing. Thanks, Joan! The gadget that I'm building is similar to an automobile radio tuner where the dial can be moved ...
by moderatelyfunky
Mon Aug 20, 2018 1:15 pm
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

Re: pigpio - run stepper many steps precisely

It looks like wave_chain may fit the bill - https://www.raspberrypi.org/forums/view ... p?p=994373
by moderatelyfunky
Mon Aug 20, 2018 12:13 pm
Forum: Python
Topic: pigpio - run stepper many steps precisely
Replies: 9
Views: 1433

pigpio - run stepper many steps precisely

I am trying to use pigpio Python interface to ramp a stepper motor up, run for a number of steps and ramp down before stopping. This is to move a nut down a lead screw many feet long to a specified position. There are four motors involved, each of which will have lead screws and nuts with their own ...

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