Cron job help! time.sleep not working.

[compuguru]

Hey guys, i have a raspberry pi that i am trying to automate my aquarium with, i have most of it figured out but am having some trouble getting my water pump to run for 5 seconds a day, this pump is used to dose chems/water treatments in small doses.

anyway, i am trying to run a script using the crontab, i know crontab is triggering the script because it works fine when i only have 1 line of code in the script file.

I need the code to turn on GPIO 19, and then shut it off after 5 seconds.

Any help is appreciated, please see the code i am trying to use below, GPIO 19 does come on but has to be shut off manually, the last line of code never runs.

Note: I have tried time.sleep(5) < without the spaces

Code: Select all

#!/usr/bin/python

import time

echo "0" > /sys/class/gpio/gpio19/value

time.sleep( 5 )

echo "1" > /sys/class/gpio/gpio19/value

[davef21370]

Why not use one of the GPIO Python modules?

Dave.

[scotty101]

Code: Select all

echo "0" > /sys/class/gpio/gpio19/value

This is not a valid python command. This is a bash script command.

Which do you want to write? Python or Bash?

[compuguru]

Can bash and python work in tandem? If not I would like to use bash, unless it is not capable of a delay.

[Douglas6]

Can bash and python work in tandem?

Not like that.

Code: Select all

sleep 5

in bash.

[compuguru]

So, remove the brackets and the number will trigger a delay for x seconds?

I'll give this a shot when I get home!

[elParaguayo]

If it's meant to be bash, it's probably also worth changing the shebang at the start of your script. It's currently set for python.

Given your description of the problem, this probably won't alter anything (as it sounds like the script is being interpreted as bash already) but it'll remove some confusion for other people!

[Douglas6]

And remove

Code: Select all

import time

It's helpful to test your cron scripts from a command line first.

[compuguru]

Thank you for the suggestions!