The best way for me to do it was to use node-red. Fantastic program for us newbies with little coding experience. Highly recommended. I’m running it on the pi that is sending the values to the MM pi. Works great.

I’ve got a program that converts Celsius to Fahrenheit for the ds18b20 temperature probe on a Pi that I’ll be putting outdoors. I’d like to use MQTT to send the output of this program to another PI with a weather station indoors. I’ve got it all setup except I don’t know how to get the output of the program which prints the converted temperature to MQTT. Any help would be appreciated.

I did find it could be done when a template was available, something like this one for Home Assistant

code_text
```climate:
   platform: mqtt
    name: "Master Bedroom"
    current_temperature_topic: "homeassistant/sensors/flair/puck/Master Bedroom-30f/Temperature"
    current_temperature_template: "{{(value * 9/5)+32}}"
    precision: 0.1

I’ve got one Pi with the DS18B20 sensor and am sending the values using MQTT to another Pi running Magic Mirror. Thanks everyone who provide these great modules. I’d really like it to display fahrenheit instead of celsius. Any help would be appreciated. And my coding skills are rudimentary!

@hengy
Well it seems to be working. What was missing from the cut and paste I did of the code was

#! / Usr / local / bin / python

Seems /usr/local/bin/python doesn’t exist on my pi. I changed it to usr/bin/python. Also
okunan means read in Turkish. I changed it back to read. I ran this in a terminal and it seems to work. Nice, I now have a screen which changes to ambient light.

Well I’ve done the wiring. I think it’s correct. I’m wiring directly with the pins on the pi.
I get the error
sudo: unable to execute ./backlight.py: No such file or directory

Here’s the code. Any help would be appreciated.

import RPi.GPIO as GPIO
import time
In gpıo.setmo (GPIO.BOARD)
#ldr reading pisi identification
pin_to_ldr = 7
def rc_time (pin_to_ldr):
	count = 0
  
	#Output on the pin for 
	GPIO.setup (pin_to_ldr, GPIO.OUT)
	GPIO.output (pin_to_ldr, GPIO.LOW)
	time.sleep (0.01)

	#Change the pin back to input
	GPIO.setup (pin_to_ldr, GPIO.IN)
	#Count until the pin goes high
	while (GPIO.input (pin_to_ldr) == GPIO.LOW):
        	count + = 1

	return count

#Catch when script is interrupted, cleanup correctly
try:
	# Main loop
	while True:
		bl = open ('/ sys / class / backlight / rpi_backlight / brightness', 'w'
		read = 0
		read = rc_time (pin_to_ldr)
		if read

I found this posting and will try to install it this week. Just use google translate to translate from its native Turkish.

http://www.ilhanakilli.com.tr/sbc/raspberry-pi-7-dokunmatik-ekran-otomatik-parlaklik/

Have you had any luck with this. I’d also like some way to change alarm times on a touch screen.