I hope this is the right section of the forum for this thread, otherwise tell me and I will rewrite this post in the correct one.
In the photos I show you there is the schematic (pcb) of a wireless remote control that turns on and adjusts the speed of a fan attached to the ceiling.
I am wondering how it works:
when a button (GPIO) is pressed the microcontroller (on the package there is "12F629 1/SM1622", I would say it is a PIC) reads it and, depending on which one was pressed, an electrical signal is sent to the receiver built into the fan that will trigger I think switches to turn on/off the light, turn on/off the fan, and adjust the speed of the blades.
I have some questions:
1) What sends the electromagnetic signal? An RFID sensor? An IR LED? Or what else?
2) Where is it in the pcb? I don't see it ... maybe it's embedded in what I think is a simple LED? (to the left of the pcb)
3) The electrical signal generated and transmitted by the remote control will have to be different and unique for each button pressed, so that the receiver will "distinguish which of the buttons has been preempted" and act accordingly. Is this done by changing the phase of the signal? the frequency? the amplitude? Imagine you are the receiver and you get the signal, you will ask yourself "if component x of the signal is like this, then I turn on the fan ... if instead it is like this, I increase the speed" etc. How is this done?
4) If my neighbor comes with his fan remote controller and tries to turn on my fan, it won't turn on. So I assume that it is not a "universal" remote controller but that each manufacturer can make his own fan that works only with his remote controller. How does the receiver recognize that the signal is coming from its own remote control? I think that this question is a very similar to question 3) ... I think it's the same principle.
In the photos I show you there is the schematic (pcb) of a wireless remote control that turns on and adjusts the speed of a fan attached to the ceiling.
I am wondering how it works:
when a button (GPIO) is pressed the microcontroller (on the package there is "12F629 1/SM1622", I would say it is a PIC) reads it and, depending on which one was pressed, an electrical signal is sent to the receiver built into the fan that will trigger I think switches to turn on/off the light, turn on/off the fan, and adjust the speed of the blades.
I have some questions:
1) What sends the electromagnetic signal? An RFID sensor? An IR LED? Or what else?
2) Where is it in the pcb? I don't see it ... maybe it's embedded in what I think is a simple LED? (to the left of the pcb)
3) The electrical signal generated and transmitted by the remote control will have to be different and unique for each button pressed, so that the receiver will "distinguish which of the buttons has been preempted" and act accordingly. Is this done by changing the phase of the signal? the frequency? the amplitude? Imagine you are the receiver and you get the signal, you will ask yourself "if component x of the signal is like this, then I turn on the fan ... if instead it is like this, I increase the speed" etc. How is this done?
4) If my neighbor comes with his fan remote controller and tries to turn on my fan, it won't turn on. So I assume that it is not a "universal" remote controller but that each manufacturer can make his own fan that works only with his remote controller. How does the receiver recognize that the signal is coming from its own remote control? I think that this question is a very similar to question 3) ... I think it's the same principle.
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