Problems with Cloud9 in reference to Issue #169

[tomek242]

#169
When I try same code which I present in Issue #169 I have the same error like bmcilw1:

Your code is running at http://localhost.

Important: use os.getenv(PORT, 8080) as the port and os.getenv(IP, 0.0.0.0) as the host in your scripts!

Traceback (most recent call last):
  File "/var/lib/cloud9/my_python/test1.py", line 10, in <module>
    PWM.start(pin1,0)
RuntimeError: Problem with a sysfs file

Question: Why the same code in Python work when I wrote it in simply nano editor and does not work in IDE Cloud9?
Second thin is: how to set direction of PWM pins?

[pdp7]

Second thin is: how to set direction of PWM pins?

PWM signal is output only. The pins do have other modes but PWM mode is always an output.

[pdp7]

Question: Why the same code in Python work when I wrote it in simply nano editor and does not work in IDE Cloud9?

@tomek242 Are you using this image: bone-debian-9.2-iot-armhf-2017-10-10-4gb.img.xz?

[pdp7]

@tomek242 What is in /var/lib/cloud9/my_python/? Did you create that directory? I don't believe it should exist on a fresh image.

I'm using the Debian Stretch 9.2 image (2017-10-17) which can be downloaded from @RobertCNelson's server.

There is this example Python program in:
/var/lib/cloud9/examples/blink.py

import Adafruit_BBIO.GPIO as GPIO
import time
 
GPIO.setup("P9_14", GPIO.OUT)
 
while True:
    GPIO.output("P9_14", GPIO.HIGH)
    time.sleep(0.5)
    GPIO.output("P9_14", GPIO.LOW)
    time.sleep(0.5)
    break

I can open and run it OK in the Cloud9 IDE. Here is a link to screenshot: https://photos.app.goo.gl/dWi2ILLFK7LS5QfB2

[tomek242]

Yes thats the same image, and i was try this same sample script :)

Btw. Robert C. Nelson take us some new images on his repository i mean images from 2017-10-29 - are they images ok? Or something is wrong with them? May I test it in my project without any risk?

I mean, how to configure the states on GPIO pins after system boot. I will use this pins to control wheels rotate on my project.

[thebrianbug]

Update: I've tried the image you guys suggested to me: #169 (comment).

When I use this image, PWM works 100% in BoneScript :). However, it does not work in Python via iCloud9 or when I run it from command line directly on the board (same error).

[pdp7]

@tomek242 Sorry, I just realized that I edited your comment instead of replying to it. Here are my responses.

Yes thats the same image, and i was try this same sample script :)

Please paste the contents of /var/lib/cloud9/my_python/test1.py here with the Insert code button. I will try running it in the Cloud9 IDE.

Btw. Robert C. Nelson take us some new images on his repository i mean images from 2017-10-29 - are they images ok? Or something is wrong with them? May I test it in my project without any risk?

The best place to look for testing images is on this eLinux wiki page:
https://elinux.org/Beagleboard:BeagleBoneBlack_Debian#Debian_Image_Testing_Snapshots

The entries on that page link to downloads on @RobertCNelson's server.

I mean, how to configure the states on GPIO pins after system boot. I will use this pins to control wheels rotate on my project.

Which pins are you using?

Are you wishing to use those pins in GPIO mode?

If so, the config-pin utility can be used to set the pin mode.

[pdp7]

@bmcilw1 wrote:

When I use this image, PWM works 100% in BoneScript :). However, it does not work in Python via iCloud9 or when I run it from command line directly on the board (same error).

Please paste the Python code you are running (use the Insert code button).

Also, I have just merged several fixes ( #183 and #184 ) so please install the latest version of Adafruit_BBIO from this repo.

[thebrianbug]

Here is my test code

import Adafruit_BBIO.PWM as PWM
 
servo_pin = "P8_13"
duty_min = 3
duty_max = 14.5
duty_span = duty_max - duty_min
 
#PWM.start(servo_pin, 50, 1000, 1)
#PWM.start(servo_pin, 50)
PWM.start(servo_pin, (100-duty_min), 60.0)
 
while True:
    angle = raw_input("Angle (0 to 180 x to exit):")
    if angle == 'x':
        PWM.stop(servo_pin)
        PWM.cleanup()
        break
    angle_f = float(angle)
    duty = 100 - ((angle_f / 180) * duty_span + duty_min) 
    PWM.set_duty_cycle(servo_pin, duty)

Here is the output

Traceback (most recent call last):
  File "/var/lib/cloud9/senior_design/pwm.py", line 10, in <module>
    PWM.start(servo_pin, (100-duty_min), 60.0)
RuntimeError: Problem with a sysfs file

How do I get the latest image from this repo @pdp7 ?

[thebrianbug]

I figured out what was going on with the sysfs file error. See my issue.

[pdp7]

@bmcilw1 wrote:

How do I get the latest image from this repo @pdp7 ?

Please see #185 (comment)

[pdp7]

@tomek242 Linux 4.14 kernel should resolve the issue of non-root access to the PWM outputs. Please try installing 4.14 kernel build by @RobertCNelson with:

sudo apt-get update
sudo apt-get upgrade
sudo /opt/scripts/tools/update_kernel.sh --lts-4_14
sudo reboot

[pdp7]

@tomek242 please build and install the master branch of this repo:

sudo apt-get update
sudo apt-get install build-essential python-dev python-pip -y
git clone git://github.com/adafruit/adafruit-beaglebone-io-python.git
cd adafruit-beaglebone-io-python
sudo python setup.py install

I have pushed commit b65cbf8 which causes pwm_start() to sleep 100 ms after export to avoid udev race condition (refer to #185).

Here is my screenshot of Python program running in CloudIDE and controlling PWM output as non-root user: https://photos.app.goo.gl/aA9ToTL5cAwgwuw83