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Why is setup True and false in GPIO?
GPIO.setup (18, True) is an incorrect use of the function and makes no sense. It should preferably be trapped as an error. True has the value 1. The value of GPIO.IN is 1 so coincidentally this set 18 to be an INPUT. Given that no voltage is set by the relay on 18 then it will be low.
A great starter hardware project using the Raspberry Pi is hooking up a simple tactile switch to the Raspberry GPIO and detecting button presses in Python. This guide will guide you through setting up the circuit with the Raspberry Pi and reading the state of the button in Python.
How does a GPIO function work on a Raspberry Pi?
A GPIO event in the Raspberry Pi Python GPIO library works by calling a Python function whenever an event is triggered. Such a function is called a callback function.
Why does GPIO say 18 instead of 18?
There seems to be a small amount of power supplied to the pin on boot as the LED lights dimly but there is not enough to trigger the relay. This is fixed after is run. GPIO.setup (18, GPIO.OUT) correctly sets 18 to be an OUTPUT. I say 18 rather than pin 18 or GPIO 18 as you haven’t specified the numbering scheme you are using.
Are there any false triggers for the Pi filter?
The pi-filter (thanks to Mariusb57) works like a charm : I never had any more false triggers since I installed it between Vcc (+5V) and the Vin input of RCWL-0516 sensor ! I wish I could now understand the exact way this ‘resistor-only’ pi-filter works as (normally) a pi-filter is made up of an inductor instead of a resistor any clue ?
Why does my ESP trigger a false trigger?
This may be due to the fact that when the ESP goes into transmit mode it draws power which causes a slight ripple in the power line which is sufficient to trigger the RCWL. The capacitor accross the power line near the RCWL mitigate this effect. Hope this helps someone …..
How to control al Relays with GPIO 18?
Use GPIO.setwarnings (False) to disable warnings. I also try to control al relays with the GPIO 18 but it is not working at all. I tried it with some others but nothing changed. the relais i all the time on and it is not turning off with the command. what is my problem? can you please tell me the problem ?