ADC.setup() Prevents Python Program from Running at Autostart

[Tomas Medina]

I am trying to write a program that reads the analog values of a sonar on the Beaglebone Black Wireless (Debian image 2017-07-01). The program runs fine if executed from the command line, but when I try to run it automatically at startup (using crontab), the program doesn't run at all (as indicated by a grep command). Here is the relevant code:

from time import sleep
import Adafruit_BBIO.ADC as ADC
ADC.setup()

while True:
    sonar = ADC.read(pin)
    print sonar
    sleep(.5)

Any help in this matter would be greatly appreciated.

[Drew Fustini]

Check out this example of how to run a script at startup:

https://github.com/adafruit/adafruit-beaglebone-io-python/blob/master/doc/run_config-pin_during_startup.md

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[Dennis Lee Bieber]

On Tue, 12 Sep 2017 12:43:26 -0500, Drew Fustini
<pdp7...@gmail.com> declaimed the following:

>Check out this example of how to run a script at startup:
>https://github.com/adafruit/adafruit-beaglebone-io-python/blob/master/doc/run_config-pin_during_startup.md
>
>On Sep 12, 2017 12:35 PM, "Tomas Medina" <to...@evatech.net> wrote:
>

>> from time import sleep
>> import Adafruit_BBIO.ADC as ADC
>> ADC.setup()
>> while True:
>> sonar = ADC.read(pin)
>> print sonar

I'd be concerned about that print statement... Where is stdout going
for a cron job?
--
Wulfraed Dennis Lee Bieber AF6VN
wlf...@ix.netcom.com HTTP://wlfraed.home.netcom.com/

[Tomas Medina]

I'm assuming you mean how I'm displaying the values. I'm not, but disabling the print statement didn't fix the problem.

[Przemek Klosowski]

On Tue, Sep 12, 2017 at 2:15 PM, Dennis Lee Bieber <wlf...@ix.netcom.com> wrote:

        I'd be concerned about that print statement... Where is stdout going for a cron job?

 

Cron jobs aren't supposed to have output. If they do, it's mailed to the owner of the job, presumably because they contain error messages for debugging.

[Mala Dies]

Hello,

Run the CRON job with EDITOR=nano crontab -e and make sure you are root. I forget what it must take to become root in our new systems. By default, the Debian Stretch Distro does not place us in the root directory. sudo -i will do it!

Seth

[Mala Dies]

Oh and Medina,

You may need to set up all your code and software in the root folder to allow for direct action in your boot.

Seth

P.S. sudo -i

[Mala Dies]

Hello Medina,

Seth here, again. Oh and dude, you can also throw all that software into the Autorun folder on Cloud 9.

Seth

P.S. Just a reminder...if you use sudo -i, you can exit out by just typing exit. That will bring you to your debian@... or whatever your name is now. You would, before the exit cmd, be root@... and not debian@... or so on. 

On Tuesday, September 12, 2017 at 12:35:33 PM UTC-5, Tomas Medina wrote:

[Tomas Medina]

All my files are already in root. I disabled the security in my Beaglebone so I can log in with root and have administrative privileges by default. I already tried crontab and it didn't run. I prefer not to use Cloud9 due to its limitations. That being said, uploading a file to the autorun folder didn't work either.

[Mala Dies]

Okay...no issue. I hope things work out. If I come across the correct way to start a program/software on boot, I will let you know.

Seth

P.S. I read about it a while back but I came up empty with my current search. They have some Debian docs. on it. I will let you know if I come across it again.

[Mala Dies]

Hello Tomas,

I just listened to Fustini in this post, https://github.com/adafruit/adafruit-beaglebone-io-python/blob/master/doc/run_config-pin_during_startup.md, by starting a service and making two uart pins available to me on boot. 

Seth

P.S. I hope things are going well in your quest. BBB!

On Wednesday, September 13, 2017 at 11:33:12 AM UTC-5, Tomas Medina wrote: