Discussion in 'Do It Yourself (DIY)' started by Ranjib, Feb 10, 2017.
There is nothing better than spending time with your children...or grandchildren (in my case).
Hi again, i have tried to modify the file duty_cycle and when saving says: error writing duty_cycle: invalif argument
and in the console with root
root@raspberrypi:/sys/class/pwm/pwmchip0/pwm0# echo 10000000 > duty_cycle
bash: echo: write error: Invalid argument
So the plot thickens..
When I try run the line provided above I got a permissions issue which really shouldn't happen with pi and sudo.
I opened it with pico using sudo and when I try to save I get:
[ Error writing /sys/class/pwm/pwmchip0/pwm0/duty_cycle: Invalid argument ]
I also tried stopping the reef-pi service and that did not help.
So something is preventing us from updating the file.
No worries at all, we appreciate the work that went into this and the ongoing support. It is the nature of Pi projects to have occasional problems!
if change permissions same problem:
pi@raspberrypi:/sys/class/pwm/pwmchip0/pwm0 $ sudo chmod 777 duty_cycle
pi@raspberrypi:/sys/class/pwm/pwmchip0/pwm0 $ ls
capture duty_cycle enable period polarity power uevent
pi@raspberrypi:/sys/class/pwm/pwmchip0/pwm0 $ sudo echo 10000000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle
echo: write error: Invalid argument
ok, i try the version 2.2 of reef-pi and work fine, but with
I installed version 2.2 and it works perfect, but ne 2.3 continues the problem
Can confirm, same for me. Will move forward with 2.2 pending a fix for 2.3.
@theatrus ^^ I suspect reef-pi/rpi pwm changes
how can i buy a
Reef-Pi Pico Controller Board (Revision D) ?????
Quite likely. It’s possible the kernel driver gets in a weird state, hence the invalid argument error. The various knobs have to be knobbed in a specific order.
If you get in the state, try rebooting the whole Pi (reboot, not reload).
Send firstname.lastname@example.org an email. He will get you all hooked up.
If I remembered @Ranjib made some updates to correct the issues @Bigtrout was seeing with the
PCA9685 pwm, which fixed those issues. I suspect something broke for the native rpi pwm, I'm running 2.2 and it works fine and never rolled to 2.3 since everything was working fine. I think the thing to call out is if using the pca9685 you probably want to use 2.3 and if using native rpi pwm use 2.2.
I was almost going to suggest that this weekend but didn't really think it would make a difference.
So, if I use a pca9685 board would I have 16 channels? and if I use the native I will only have 2?
That is correct
Have you thought as well as the pH sensor add to monitor salinity? using the module EC EZO
Just a doser reminder. Especially if you are using cheap Chinese peristaltic pumps. Set a timer to check calibration every so often. I have been dosing with reef-pi flawlessly for several months now. I did a random Alk test today and my levels where 9.6 from 8.4. I checked calibration on the pump and had to adjust it 10% slower to get back on track.
EZO pH sensor is supported already. I felt the EC/Salinity sensor is not so important, given ATO is in place. Though it was not planned, I am actually working on getting the DO sensor support, because some folks in University of Alabamae is using reef-pi to monitor some experiments, they need it and I would love to support them.
Oooh, maybe Reef-Pi will be listed in future journals under methodology! Thanks for making an effort to help the university!
Separate names with a comma.