TEMPERATURE SENSING

[alanhendo]

When using the one wire system I had a problem with some sensors not showing up on the device list - but were definitely listed in the code with their 12 digit unique identification . After much research the cause of the problem is that Domoticz apparently only discriminates between the devices using the last 4 digits. I had bought 20 devices, all unique but with identical last 4 digits. I then bought a further two only to find they too had the same four digits. I suspect that this is because they were all in the same manufacturing run.
Is there a way to identify the 12 digits and resolve the problem?

[Diewe]

I do have the same problem, I bought 10 DS18B20 sensors, and all of them are identical on the last 6 characters.
Is there a "workaround"?

Dietmar

[adeibiza]

i use a python3 script: (originally used on 2 ds18b)

Code: Select all

import os
import glob
import time
from datetime import datetime
import urllib.request


########################
# Set up all variables #
########################

#allows use of the sensors 
os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')
base_dir = '/sys/bus/w1/devices/'


#initialize variables for counting hot readings
i1 = 0



#insert device serial numbers here
#sn2 = '28-3c01b55624db' 
sn1 = '28-3c01b5562afc'


#initialize all of the directories for the sensors
device_file1 = glob.glob(base_dir + sn1)[0] + '/w1_slave'


idx1 = 3
url_json1 = "http://192.168.1.154:8080/json.htm?type=command&param=udevice&idx=" 

idx2 = 122
url_json2 = "http://192.168.1.150:8080/json.htm?type=command&param=udevice&idx=" 



################################
# Routines to read each sensor #
################################
#Read Sensor 1
def read_temp_raw1():
	f = open(device_file1, 'r')
	lines1 = f.readlines()
	f.close()
	return lines1

def read_temp1():
	lines1 = read_temp_raw1()
	while lines1[0].strip()[-3:] != 'YES':
		time.sleep(0.2)
		lines1 = read_temp_raw1()
	equals_pos = lines1[1].find('t=')
	if equals_pos != -1:
		temp_string1 = lines1[1][equals_pos+2:]
		temp_c1 = float(temp_string1) / 1000.0
		temp_f1 = temp_c1 * 9.0 / 5.0 + 32.0
		return temp_c1






#############
# Main Loop #
#############

while True:
	
	temp1 = read_temp1()

	print('temp1 '+str(temp1))

	# cmd1 = url_json1  + str(idx1) + "&nvalue=0&svalue=" + str(temp1)
	# hf1 = urllib.request.urlopen(cmd1)
	# hf1.close
	# time.sleep(1)
    
	cmd2 = url_json2  + str(idx2) + "&nvalue=0&svalue=" + str(temp1)
	hf2 = urllib.request.urlopen(cmd2)
	hf2.close
	time.sleep(1)
	

	
	time.sleep(10)