Need information on how to control a microcontroller wirelessly

[Victor43]

Actually the title should read "How to control devices wirelessly"

Firstly I apologize for posting in the wrong group or forum all together.

Ok I am very new to the electronics terminology so please bear with me if I don't choose the right words. I would like to learn for just the sake of learning and to satisfy my curiosity on how experts like yourselves would carry out such a project. So what we have is say any device like an everyday fan (used to cool you on a hot summer day). Ok then how would someone add a say a component which would allow one to control that device (in this case being a fan) wirelessly ? Now I know that fans do come with a remote these days but this is besides the point (the device could be really anything like a Microwave, Radio, Central Air (thermostats), a portable heater and etc, anything else really). So if someone wanted to control the behavior of that device like our fan (make it turn on, off, higher speed, lower the speed) how can this be done ? How is it possible to add a new electronic component (a wireless receiver) to an existing circuit board that would allow someone to control this fan remotely (wirelessly) ? Please the fan was the only example that I could think of even though I know you can buy one with a remote control. I just want to understand how some one can carry out such a project.

Would you need to understand the existing datasheet of the existing controller to start off ? If so then how can you modify the existing circuit board to add a wireless receiver chip ? My only question is how can someone modify the existing design in order to accomplish what I asking about ? Do you replace an existing chip (of course one would need to understand the existing schematics) with your own that has the wireless receiver chip already built and ready to go ? To replace the existing chip would you not need to know how the existing Miicrocontroller works and its routines are in order to add extra features (like the ones being sent via wireless receiver ? s it fairly easy to have one of these microcontrollers with the embedded wireless receiver manufactured ? Are these MicroControllers found on any electronic item fairly standard in the routines that they use ?

Thanks for taking the time to read this post. Hopefully I am have made my self clear but if not I would be more then happy to explain myself better.

Victor

 

[carbonzit]

I think your heading ("Need information on how to control a microcontroller wirelessly") is a bit misleading; what you seem to be asking about is controlling devices (like fans) wirelessly.

In any case, look into the X10 protocol for wireless remote control (like this page, lots more like it out there). It may be just what you need (or not).

 

[Victor43]

Thanks carbonzit.

Appreciate the reply. Would you know how is it possible on how to add such a chip to an existing IC ? If the original design of the circuit board did not intend for the board to support addditonal components then how is it possible then ? I am puzzled by this question ? I apologize for the confusing title. I will try to see if I can fix that.

Victor

 

[carbonzit]

No, with X10, you don't mess with ICs at all: it allows you to control anything that plugs into your house's outlets wirelessly, simply by plugging it into an X10 controller. Is this what you want to do? or are you set on trying to wire something into an appliance's control board?

 

[Victor43]

No, with X10, you don't mess with ICs at all: it allows you to control anything that plugs into your house's outlets wirelessly, simply by plugging it into an X10 controller. Is this what you want to do? or are you set on trying to wire something into an appliance's control board?

Thanks again for the helpful reply. I actually wanted to find out if there was a way to modify an existing PCB board that contains circuits....Take an old fan and just for the fun of it introduce a wireless receiver chip and a method of sending commands to the already existing microcontroller that tells it to increase the fan speed or lower it or turn off the fan. I want to find out how to modify an existing IC with what I am interested in doing/ Perhaps its not possible....?

Victor

 

[4pyros]

You cannt just change a chip. Every device is differant. You would have to add a RF module, a controller, and a power switching device to everything and thay would be differant depending on what the device to be controled is. If you wanted you could make modules to turn stuff on and off like X10, but thats only like pulling the plug out of the wall.

 

[Jugurtha]

Hello,


To tell you the truth, you confused the hell out of me.

(Modify a circuit board ? Which one are you talking about ?) Anyway..

I have never done such a thing, so I know as much as you do about it.. If I was you and wanted to do this, I would formalize the problem:

I want to control the Device D wirelessly... I then need to :

a-Transmit the command from point 1.

b-Receive the command in point 2.

c-Process and Execute the command. (You won't plug a motor to a NAND gate ... You'll need some sort of POWER controlled by a tiny signal.. Just like a MUSCLE is controlled by a small signal from your brain)


We didn't discuss the details, because whatever they are, they'll all use these three steps in my opinion. It all boils downs to transmit, receive, process and execute.

I can be inspired by TV remote controls for example. Push a button, then a chip that transmits (IR for example with a chip that would transmit a train of impulses, a sequence of bits or something)

And then, I would do a Google search with something along the lines : ir transmitter chip remote control.

Actually write it ad litteram.

I would stumble on this link : https://jap.hu/electronic/codec.html

And this one https://jap.hu/electronic/infrared.html

And I would search some things like that.. (I opened some TV remotes, I forgot the chip they used though.. So I Googled "TV remote control chips". I found this link

https://www.howstuffworks.com/inside-rc.htm

I clicked, the author talked about a chip the TA11835.

I Googled that (TA11835), etc , etc...

 

[carbonzit]

Ok then how would someone add a say a component which would allow one to control that device (in this case being a fan) wirelessly ? Now I know that fans do come with a remote these days but this is besides the point (the device could be really anything like a Microwave, Radio, Central Air (thermostats), a portable heater and etc, anything else really). So if someone wanted to control the behavior of that device like our fan (make it turn on, off, higher speed, lower the speed) how can this be done ?

Re-reading your original post, I get what you're after: being able to control an appliance (e.g., microwave oven) wirelessly, and being able to do more than just turn it on and off remotely. So X10 is out the window.

This is both a good question and a naive one. Good because it is in the realm of possibility; naive because it would involve a tremendous amount of research and development.

To satisfy your curiosity, let me explain how this could be done. I'll choose to use RF (radio frequency) control, rather than IR (infrared) control, since IR remotes require a line of sight (your TV has to be able to "see" your remote in order to respond to it).

RF remote control requires, obviously, a transmitter and a receiver. I'll focus on the receiver end. There are many more or less off-the-shelf RF remote control systems available. They give the designer a single chip which

• Receives the RF signal from the antenna
• Tunes and amplifies the signal
• Demodulates the signal (separates the signal from the carrier)
• Massages the signal so it can be used by the remote-control circuitry

The demodulated remote-control signal can then be run through the remote-control logic circuitry. So, for example, a certain signal received by the RF module could control the microwave's heat level.

So far, I'm writing this as if this is easily possible. But, unfortunately, it's not.

Implementing the RF "link" (transmitter--> receiver--> logic signals) would actually be the easy part here. The difficult (or near-impossible) part would be tying into the appliance's own controls to implement the function (like raising and lowering the heat level). The problem is that these devices are controlled by logic circuitry which, in the case of more complex devices like a microwave, may include a microcontroller. Even if you knew exactly how that worked (you had schematics and the code which runs on the microcontroller), it would be very hard to tie in an outside signal to control it. If you didn't have that information (no schematic or code), then the task is pretty well nigh impossible.

Let me ask a simple question: what, exactly, are you wanting to do here?

 

[Victor43]

You cannt just change a chip. Every device is differant. You would have to add a RF module, a controller, and a power switching device to everything and thay would be differant depending on what the device to be controled is. If you wanted you could make modules to turn stuff on and off like X10, but thats only like pulling the plug out of the wall.

Thanks for the reply. Ok then is it possible to add these new components to the IC in order to control the device wirelessly ? I've actually read a little about the X10 module and even called the company but that is not what I am researching. Please note that this is not an actual exercise that I intend to take on. Its beyond but I was only wanting to find out if it were possible and if so how would it be done.

Thats all....and thanks again for the reply.

Victor

 

[Victor43]

Re-reading your original post, I get what you're after: being able to control an appliance (e.g., microwave oven) wirelessly, and being able to do more than just turn it on and off remotely. So X10 is out the window.

This is both a good question and a naive one. Good because it is in the realm of possibility; naive because it would involve a tremendous amount of research and development.

To satisfy your curiosity, let me explain how this could be done. I'll choose to use RF (radio frequency) control, rather than IR (infrared) control, since IR remotes require a line of sight (your TV has to be able to "see" your remote in order to respond to it).

RF remote control requires, obviously, a transmitter and a receiver. I'll focus on the receiver end. There are many more or less off-the-shelf RF remote control systems available. They give the designer a single chip which

• Receives the RF signal from the antenna
• Tunes and amplifies the signal
• Demodulates the signal (separates the signal from the carrier)
• Massages the signal so it can be used by the remote-control circuitry

The demodulated remote-control signal can then be run through the remote-control logic circuitry. So, for example, a certain signal received by the RF module could control the microwave's heat level.

So far, I'm writing this as if this is easily possible. But, unfortunately, it's not.

Implementing the RF "link" (transmitter--> receiver--> logic signals) would actually be the easy part here. The difficult (or near-impossible) part would be tying into the appliance's own controls to implement the function (like raising and lowering the heat level). The problem is that these devices are controlled by logic circuitry which, in the case of more complex devices like a microwave, may include a microcontroller. Even if you knew exactly how that worked (you had schematics and the code which runs on the microcontroller), it would be very hard to tie in an outside signal to control it. If you didn't have that information (no schematic or code), then the task is pretty well nigh impossible.

Let me ask a simple question: what, exactly, are you wanting to do here?

Thanks for understanding my question. That is exactly what I am interested in learning how it is done. The reason that I am interested in such an area is because I find it interesting in how it can be done. Whether it is an impossible task is irrelevant to me because I don't plan taking such a project because its point less and moreover I don't have the knowledge or background. What I was interested in was finding out if it is possible and if so what would it involve. I am under the opinion from the above replies that the Circuit board would have to be modified in order to receive the RF signal as you have very nicely described in your reply. What I don't quite understand is how the second part of your reply can be done. What I mean is how can the RF signal once demodulated is converted into a command that the microcontroller of the mainboard can understand is being implemented on the board. Can all be done with a single chip which includes the antenna, receiver, demodulator and embedded controller) which would accomplish all of these functions ? If it can be done then where can the chip be placed ? Does not one need to know the schematics of the mainboard of the host appliance in order for this project o be possible ? Also is there a universal language that is implemented in order for this so called "all-in-one chip" can communicate with the host microcontroller ? I think there is a datasheet for all items that are manufactured today that explains the logic of the chips used for any electronic item ?This is my theory and please correct me if I am wrong or completely off base....

Appreciate all the replies....

Victor