Executing python script, reading a value(temperature) and importing the value to openHAB

Setup, Configuration and Use Scripts & Rules
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1

Hello guys,

I’m pretty new to openHab and I’m working for a study project on a raspberry pi. I have a problem and I’m pretty sure it’s a little tiny problem what drives me nuts. I looked out for it on the world wide web. I followed there suggestions and tips, still not working.
As you can see in the topic I want to get a certain value out of my python script and make it visible on the openHab interface.

Here is my home.sitemap:
sitemap home label=“Home”
{
Frame label=“Home”
{
Switch item=TestLED
Text item=TestTemp
Text item=TestText
}
}

and my home.item:
Switch TestLED {gpio=“pin:21”}
Number TestTemp “TestTemperature [%.0f °C] (home) {exec=”<[/usr/bin/python /opt/openhab/configurations/scripts/lm75_TempSensr.py temperature:1000:REGEX((.?))]"}
Text TestText “TestText [%s]” (home) {exec="<[/usr/bin/python /opt/openhab/configurations/scripts/testtext.py:1000:REGEX((.?))]"}

As you can see in TestText I just wanted display a simple string from a python script. Nothing works. It has to be something very simple I guess.

I hope you can help me. Thanks in advance

Python Script “testtext.py”
#!/usr/bin/python

print “Hello”

Python Script “lm75_TempSensr.py”
#!/usr/bin/python

from subprocess import Popen , PIPE
from time import sleep

SLAVE_ADDR = 0x48
DELAY = 30 #in seconds

def main():
try:
while True:
p = Popen([‘i2cget’ , ‘-y’ , ‘1’ , str(SLAVE_ADDR) , ‘0x00’ , ‘w’] ,
stdout=PIPE)
output = p.stdout.read()
temperature = getTemperature(int(output , 16))

		print "Current temperature is %s degree celsius" % (str(temperature))
		print "Waiting " + str(DELAY) + " seconds..."

		sleep(DELAY)
except KeyboardInterrupt:
	print "Execution canceled by user."

def getTemperature(rawData):
""“
Note: You’ll get data in reverse order from sensor:
|low byte|high byte|
0x80|0E
”""
degrees = rawData & 0xFF #cut high byte off, get low byte000
degreesAfterDecimal = rawData >> 15 #shift msb to lsb place

if (degrees & 0x80) != 0x80:	  #msb in low byte is 0 -> positive temperature
	return degrees + degreesAfterDecimal * 0.5
else:	#msb in low byte is 1 -> negative temperature
	#calc two's complement
	degrees = -((~degrees & 0xFF) + 1)
	return degrees + degreesAfterDecimal * 0.5

if name == “main”:
main()

2

Ok…i solved by my own xD

I’m trying to delete my post, but no can do.

Thx anyways cheers

3

Instead of deleting, tell us how you fixed it on your own so others may benefit. Was it a permissions problem? A path problem?

4

It was that simple, so I guessed it’s not worth mentioning it. But yeah, you are right.

I just changed the keyword to STRING, since my python script uses print as an output.

String TestTemp "TestTemperature [%s °C] <temperature> (home) {exec="<[/usr/bin/python /opt/openhab/configurations/scripts/lm75_TempSensr.py:1000:REGEX((.*?))]"}

That was pretty much it

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