System design ideas [closed]

Question

I want to build a system where it controls 16 devices' power by linux commands. My thinking is to use power transistors and microprocessor but I am new to system design. How can I control the power transistor as a gate with a digital signal from a microprocessor?

My idea is to somehow figure out that part, have 1 register each called the switch status(on or off) for all 16 devices. Then all I do is from the main computer to read and write the register value. What kind of data communication method is good for this problem? Ethernet is out because the network switch is full.

Thanks,

Answer 1

If you just need simple switching, it might be practical to use an existing solution such as an Arduino MCU or similar and a 16 channel relay daughter board (shield) to suit. This will give you a simpler coding mechanism at the MCU and plenty of options to trial for the Linux to MCU communication if you’re running the Linux on a laptop or desktop machine.

If you running Linux on a small system on a module (e.g., Raspberry Pi) then you would be able to connect a similar relay daughter board (hat) directly to it.

Answer 2

USB relay boards are common, inexpensive and easy to use, even under Linux. Being USB they could work with a PC or other Linux platform.

Here’s the CRELAY project on GitHub: http://ondrej1024.github.io/crelay/

Answer 3

Cho, there is no way I can answer this question as it is. I think the best place for you to start is what are the 16 devices, a LED, a Mega motor?? Are there tolerances involved, timing etc. Posting links to the technical side of the hardware devices helps all of us a lot. Are you writing a custom program for Linux or does one already exist! If one exists what is it and post a link to it. By control do you want on/off or something else such as PWM. How is the Linux machine going to control the I/O (Input/Output). Do you want to control the hardware with Linux or an external controller such as an arduino. Do you want to communicate with WiFi since ethernet is out. FYI You can get a small desktop switch, plug that into your main switch then plug your computer into the switch and have some open slots. How compute intensive is this, simple control could be done with a Pi and some software, it comes with Linux. I would start by listing what you want it to do and what will it do it with. Then start searching for the appropriate hardware. Please understand there are lots of answers for each question you have and what device is best, the final decision is yours alone (with our help of course).