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Install the tfmplus python module <python -m pip install tfmplus>. The process will also install pyserial, which is required. Then get the example script tfmp_test.py out of the python/lib/site-packages/tfmplus/src/tests/ folder to see how the module works. Note: This module uses the RPi GPIO15/Rx and GPIO14/Tx to connect the TFMPlus.


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You can not connect multiple serial devices to an interface (although it may be possible with additional circuitry to multiplex devices - only one can work at a time). You can of course SEND to multiple devices but only receive from one.


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Try setting force_turbo=1 in config.txt. This will disable dynamic frequency scaling of the CPU. I have had four devices (all my three Zero W devices and one Raspi 4) which used to freeze, the Zeros when the Pi Cam was connected (and used to create timelapses), then they froze randomly after a couple of hours or after a couple of days and the Raspi 4 under ...


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Using the following wiring diagram: https://gpiozero.readthedocs.io/en/stable/recipes.html?highlight=distance#distance-sensor With the code from https://github.com/makertut/raspberry-hc-sr04 : (NOTE: code requires TRIG and ECHO to be swapped to match circuit) import RPi.GPIO as GPIO import time GPIO.setmode(GPIO.BCM) TRIG = 24 ECHO = 23 print "...


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You appear to be asking us to debug some random tutorial you found on the internet which you may or may not have followed correctly. Try https://gpiozero.readthedocs.io/en/stable/recipes.html?highlight=distance#distance-sensor If this doesn't work you need to post details of your setup.


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You asked, "How should I interface a solenoid to a RPi GPIO input?", and solicited some feedback on the schematic in your question: Does the optocoupler circuit look like it will work (without destroying the GPIO)? Are there any potential pitfalls I have missed? Is there a more sensible approach to detecting the doorbell press? General Answer: ...


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As a minimum you should be discussing this with your IT support at work. Never trust free advice from the Internet where security and privacy is involved :-) Saying that, here is my free advice: The simplest way would be to use a broker based on the Internet that you can reach both from home and work. A search will turn up a few free ones (I like Adafruit ...


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You can have several solutions for your problem. With an Access Point You can create a wireless network (with an Access Point you can also have a DHCP server giving IPs to the devices - The Raspberry PI or the Arduino receiving the signals should have a static IP address) and all the devices will connect to that access point. Using the Raspberry PI as an ...


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This is an EE Question, not Pi specific. What you propose should work (depending on current transfer ratio of opto-isolator - which should be adequate). I can see only one potential issue - the snubber diode may impact on the ding on release. If so, you could protect the opto-isolator by connecting the diode across the opto-isolator input (D2 in your diagram)...


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Regarding the problem with the BME280...don’t replace cmdstring[i] = val with cmdstring[i] = str(val) but with cmdstring[i] = chr(val) That worked for me.


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The Voltage was too low. Now I draw electricity from another socket and everything is fine.


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