Orange Pi Zero PWM

[Denis Periša]

I have some servo motor I would like to start but cannot find any info on how to do it. Is PWM available in Pi PC or Pi Zero?

 

Thanks

Edited March 25, 2017 by zador.blood.stained
Merged 2 threads with the same topic (Orange Pi Zero PWM)

[nopnop2002]

There is /dev/pwm in nanopi.

 

nanopi@nanopim1:~$ ls /dev/p*

/dev/ppp  /dev/psaux  /dev/ptmx  /dev/pwm

 

 

A sample code is here.

https://github.com/friendlyarm/matrix/blob/master/demo/matrix-pwm/Matrix-pwm.c

 

http://www.friendlyarm.net/forum/topic/6810

[zipzit]

 

There is /dev/pwm in nanopi.

 

nanopi@nanopim1:~$ ls /dev/p*

/dev/ppp  /dev/psaux  /dev/ptmx  /dev/pwm

 

 

A sample code is here.

https://github.com/friendlyarm/matrix/blob/master/demo/matrix-pwm/Matrix-pwm.c

 

http://www.friendlyarm.net/forum/topic/6810

 

I'm trying to understand how you get from point A to point Z via that matrix repository at Github.  

 

That repository is intended "Nanopi2/Fire/M2" devices, yet the Orange Pi Zero is an Arm H2 device.  Remember the orange pi zero is listed as the topic for this posting.   Is the Orange Pi Zero Arm H2 really a Nanopi2 / Fire or M2 device?  How do you know that? Are these things the same? (I'd refer to the readme.md sheet at the matrix repository, but alas, that doesn't exist... sigh.)

 

Orange Pi Zero = Arm H2 Quad-core Cortex-A7 1.2Ghz.

Raspberry Pi Zero =A Broadcom BCM2835 application processor with 1GHz ARM11 core

 

(Note: no offense intended here..  I'm struggling to understand how to address the pins on the Orange Pi Zero, and I'm more than confused here...  Any hints or links to help gain and understanding? Many thanks --Zip)

[Denis Periša]

yup. but I read somewhere that 4.9 kernel should have pwm support for h3/h2 devices. Yet, I don't see it.

[zador.blood.stained]

yup. but I read somewhere that 4.9 kernel should have pwm support for h3/h2 devices.

It has the support, but it's not activated by default since hardware PWM is supported only on PA5 pin, which is used bt default serial console (UART0). So it requires some DT modifications which include moving default debug console to a different UART port.

[martinayotte]

Just a suggestion : maybe it is better to add small PCA9685 board attached to an I2C bus, you will get 16 PWM 12bits channels for few bucks.

[borombo]

how about software pwm? found this code in another site:

 

#include <wiringPi.h>

int main () {
  wiringPiSetup();
  int t_on, t_off;
  int d, i;

  d= 100 ;

  t_on= 50 *d;
  t_off= 50 *( 100 -d);

  for (i= 10 ; i!= 0 ; i++) {
    digitalWrite( 1 , LOW);
    delayMicroseconds(t_on);
    digitalWrite( 1 , HIGH);
    delayMicroseconds(t_off);
  }
  return ( 0 );
}

[B.K.O.]

this guy figured it out with PCA9685 but what do we have to change to drive servos

[tcmichals]

this guy figured it out with PCA9685 but what do we have to change to drive servos

Here is a how-to for servos, yes it is for micro-python, but it provides info on how to set it up and values. 

https://learn.adafruit.com/micropython-hardware-pca9685-pwm-and-servo-driver/software

[Cloud Peng]

I could not found pwm folder in the "/sys/class".

so, how to enable pwm in orange pi zero?

[Igor]

https://forum.armbian.com/index.php/topic/2344-pwm-on-allwinner-h3/

 

And use this search engine to get other posts regarding pwm:

https://www.armbian.com/search_gcse/

[Cloud Peng]

I am orange pi zero (H2+, 26 pin gpio), it as same as other ?

[iboguslavsky]

There is a new PWM driver available here (uses UART0_RX pin on the UART breakout header):
 

https://github.com/iboguslavsky/pwm-sunxi-opi0.git

 

Have a look at the examples also.

[zador.blood.stained]

I tested PWM on mainline too, will push a DT overlay to enable it soon.

[Sergey Kravtsov]

Hi all, I forked PiZyPWM library, so now we got Python PWM library for Orange PI. Tested on Orange Pi Lite with motor drivers. Feel free to use and fork https://github.com/evergreen-it-dev/orangepwm