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Comment by MrEfficiency | Hacker News Reader

Can anyone explain a real world use?(even a DIY use)

What would you use Linux for when embedded systems usually are written in mostly C.

Easier libraries and access to web? I cant quite understand how this can be used.

I am working on industrial level sorting machine. That machine use Linux device to control other subsystems (cameras, conveyor belt controller, various servos and what not). As number of components in systems grow you want to have single place for all the logging, handling user inputs (both local and remote), calibration and even system upgrades.

Yep, write all of your lower level components in C to run on PICs (or HDL on FPGAs, either way you get high reliability) and have those interface with larger systems that run higher level software to display sensor data and offer a control panel to command the actuators in the system. Just like in a car, the collision detector runs fast low level C but it feeds data over CANbus back to the ECU which is probably running an RTOS and sends that sensor data to the head unit which probably runs some sort of Linux-flavor to blink an icon on the reverse camera video feed.

Not everything is written in C. On a project I recently worked on we opted for Linux on the embedded platform to support some 3rd party tools and allow ourselves to work in easier-to-prototype languages.

Additionally, the management of the device is now “just Linux”, which is fairly Elmore well known.

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In retroperspective, I don’t know if I would do it in the future. There are definite advantage in using Linux, but there is also a lot of work involved in understanding Linux and keeping track of the platform. That is true for a simpler OS, but I feel it might be more manageable.

For me? I can have a solid, partitioned filesystem like ext4 running on NOR or NAND flash. I don't have a decade to write my own and make it as stable as what's already out there.

I can also have the system live-mounting USB flash drives (useful for logging and field upgrades) and reading/writing FAT16/FAT32/NTFS out of the box. If I wanted to tack a SATA drive on there, I can do that too.

Oh yeah, and I get a bash shell to manipulate it all on the target device. That's another couple of years saved.

Getting a lot of drivers, a functioning network stack and all those other neat things in one package is really comfortable. And if it is connected to the internet (and an actual product) it might need an update, which should be easier to do with a full-fledged system underneath it then writing everything yourself. Sure it is overkill for a lot of stuff, but as IoT grows by the second there are more than enough use cases for embedded linux

Fantastic platform on which to base a synthesiser, music effects module, or some other such creative device.

The synths from Modal Electronics are some good examples of what you can do with an embedded Linux system .. they're using a $25 part as the prime host for their OS, for example ..

Yeah, that's one of the main things I'm looking at this for. I'm working on some new synthesizer code (written in Rust). If someone else is looking to make an inexpensive audio board with this part, we should talk.

I'm in that business and am currently actively working on the same sort of project. Maybe we should talk... (Email is in my profile..)

Hey - just to ping you on this, your project sounds pretty interesting - any chance you're interested in some feedback/collaboration from another synthesist? I've been in the game for some time now and your project sounds very interesting - will you put out some info on it some time soon?

Developer time is expensive. Embedded guys aren't as cheap as python/javascript programmers. If you can grab an off-the-shelf solution that, say, already runs android, you can pay a high-school graduate to whip up an android app and have your embedded product on the market for less time and money.

That said, as an embedded developer, I think there are a lot of bad products thanks to this mentality. But it is the future and it's one reason I try to keep my skill set up to date.

> Embedded guys aren't as cheap as python/javascript programmers

Not sure this is true. It should be the case, but afaik the salary polls don’t support that.

Depends on the area and lots of factors. I only know that in San Diego I had to take a job for low 140's as an embedded guy and I could have leveraged by Django experience to make over 10k more if I wanted to pigeonhole myself as a Django guy. I'm regularly tempted to go into devops because the job is generally easy and the pay seems to be pushing 200k around here.

Can't speak to this particular processor, but as far as why use Linux? Yes, it's about working at a higher level of abstraction.

I'm right now finishing up a freelance job: a pump controller that could easily be done in C on an Arduino.

I chose to use an RPi programmed in Python because I could eliminate a bunch of pushbuttons, the associated wiring and a complex menuing system by using a touch screen and a Tk GUI. In this case it's about getting the job done with minimum development effort; the BOM cost is pretty much irrelevant.

Remember, the term "embedded system" encompasses a huge amount of variation in project complexity.

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