3 ms·

As an aside, I really wish that these boards would include more than two PWM outputs. The Raspberry Pi has two as well, and it feels really limiting. Analog con

by qchris 6y ago

As an aside, I really wish that these boards would include more than two PWM outputs. The Raspberry Pi has two as well, and it feels really limiting. Analog control instead gets farmed out to microcontrollers, when you could probably make it work with a single board if there were more pins to work with.

Teknoman117 6y ago
I used to love the beaglebone for that. Run application logic on the main arm core, farm the microcontroller stuff out to the embedded PRU microcontrollers (which could access all the IO functions). Still a single board solution.
- qchris 6y ago
  I agree-as far as I know, the BBB had something like 8 PWM channels. I'm not saying you need all of them, but at least 4 seems somewhat reasonable.
Youden 6y ago
I'm curious, what do you do with so many PWM outputs? I just play with electronics for side projects but stick to digital for everything, so I'm wondering what I'm missing out on.
- qchris 6y ago
  Honestly, I'm still mostly getting started in the area as well, but I'm looking to use them for motor control. An example of this would be this paper [1], which I'm hoping to replicate to some degree, but requires at least 4 PWM outputs. I'm currently planning on using an Odroid-C4, which has 6 PWM outputs. But the work I've needed to put into that in order to get a motor controller working was way more than I needed than for a RPi4b, since libraries for it already exist for the Pi vs needing to re-write them for the Odroid board. It would have been cool to try it with an open-hardware board as well. But it's not just quadcopters--a lot of other projects like rovers or position control with multiple stepper on different axes benefit from extra PWM, and doing it in software can lead to too much jitter, so the hardware timers are necessary. [1] https://www.diva-portal.org/smash/get/diva2:946992/FULLTEXT02 https://www.diva-portal.org/smash/get/diva2:946992/FULLTEXT0...

by qchris 6y ago

Teknoman117 6y ago

I used to love the beaglebone for that. Run application logic on the main arm core, farm the microcontroller stuff out to the embedded PRU microcontrollers (which could access all the IO functions). Still a single board solution.

qchris 6y ago
I agree-as far as I know, the BBB had something like 8 PWM channels. I'm not saying you need all of them, but at least 4 seems somewhat reasonable.

Youden 6y ago

I'm curious, what do you do with so many PWM outputs? I just play with electronics for side projects but stick to digital for everything, so I'm wondering what I'm missing out on.

qchris 6y ago
Honestly, I'm still mostly getting started in the area as well, but I'm looking to use them for motor control. An example of this would be this paper [1], which I'm hoping to replicate to some degree, but requires at least 4 PWM outputs. I'm currently planning on using an Odroid-C4, which has 6 PWM outputs. But the work I've needed to put into that in order to get a motor controller working was way more than I needed than for a RPi4b, since libraries for it already exist for the Pi vs needing to re-write them for the Odroid board. It would have been cool to try it with an open-hardware board as well. But it's not just quadcopters--a lot of other projects like rovers or position control with multiple stepper on different axes benefit from extra PWM, and doing it in software can lead to too much jitter, so the hardware timers are necessary. [1] https://www.diva-portal.org/smash/get/diva2:946992/FULLTEXT02 https://www.diva-portal.org/smash/get/diva2:946992/FULLTEXT0...