[jsheard]

The situation with ARM hasn't changed much unless your budget stretches to Amperes stuff, but the big change is that x86 SBCs and mini-PCs have gotten very cheap, and of course those Just Work with any Linux distro or even Windows. The Intel N100 is incredibly capable for the price.

[KaiserPro]

> The Intel N100 is incredibly capable for the price.

Hard agree, I have one and I love it. Its currently doing the VM work of what a £10k server did in 2012.

But if I want GPIO, and or battery powered things with linux, then the pi is the way forward still.

Anything else, and a pico/esp32 will do well.

[jsheard]

TBH for projects that need GPIO I would be inclined to use an RP2040 or similar hooked up to USB, then any machine can be used as the host. That's pretty much how the Pi5 works anyway, the GPIOs are driven by the RP1 southbridge which is more or less an overgrown RP2040.

[Aurornis]

> TBH for projects that need GPIO I would be inclined to use an RP2040 or similar hooked up to USB, then any machine can be used as the host

Two separate platforms connected over USB is substantially more complicated, expensive, power hungry, and consumes a lot more space.

The value prop of SBCs is that they're compact and you can do low-level work in a single package. Connecting an RP2040 to a PC and writing software for both is the opposite end of the complexity spectrum.

[moffkalast]

Yeah but why aren't there more boards with a built in coprocessor like that given how cheap they are now? Iirc only Lattepanda and the Pi Foundation make these sort of boards, and the former is overpriced beyond any common sense.

[jsheard]

Keeping the GPIO interface separate does have its advantages, if you accidentally explode a GPIO pin on an external RP2040 board then you've lost a couple of dollars instead of an entire >$50 SBC.

It doesn't have to take up much space either: https://www.waveshare.com/product/rp2040-one.htm

[moffkalast]

If USB is involved you can't really make a production ready system with it. At least they could put some proper ZH or whatever connectors for UART that don't unplug when you look at them wrong. That's one of the things they did right with the Pi 5 at least.

[varispeed]

What kind of GPIO you need? If you need slow (under 1MHz) you can easily slap some USB to GPIO device and Bob's your uncle.

[tombert]

Any reason you can't do GPIO with the ESP32? I've had pretty good luck with GPIO in NodeMCU.

[KaiserPro]

I do! as I said the pico/esp32/rp2040 are useful tools to have lying around. I'm currently using one to be a stepper controller for a project I'm doing now.

However the best thing about the Rpi GPIO stack is the support. If I google "how do I do x with y on pi" I will get lots of resources, along with the official docs (the rp2040 docs are great by the way) and a bunch of hardware that is mostly plug and play.

[tombert]

Yeah, fair; there's something nice about the fact that the Raspberry Pi is "just Linux"; it's not some attempt at an embedded version of POSIX.

You have the full Linux kernel and packages to play with, the GPIO stuff (if performance isn't a huge deal) can easily be controlled by simply writing to files, meaning that you can do quasi-embedded stuff in basically any language you want, or at least any language that has an ARM port to Linux, which is basically everything nowadays.

Still, I'm quite partial to the ESP32 with NodeMCU just because the power consumption is so ridiculously low and NodeMCU + Lua is pretty easy since it has full GC and gives you a node.js-style callbacks that I think are generally easier to work with than doing it myself in C. Most of my embedded projects have moved to the ESP32 as a result.

[Marsymars]

The top-end Alder-Lake-N N305 is good too! Double the threads, and probably a bit worse performance-per-dollar.

[graphe]

When do you use GPIO with Linux?

[KaiserPro]

Something with higher order processing requirements.

the rp2040w has wifi, micropython and a bunch of GPIO, all running at low hundreds of megs. Great for motor controllers and that sort of stuff. I use them a lot for the sort of things I would have used Pis for.

However thats because its python. If you want rust, or javascript, then the pi is probably still a good option (I know there are native ports, but they are not as common or easy. )

But if you want computer vision, or, can't be arsed with micro based programms, then pi is where its at.

The other type of application is home assistant. I have an N100 running HA in a VM. It would have been easier with all the home security stuff to have it running on a pi directly. (yes you can use esp32 as binary sensors, which is what I do, but its expensive to have things that aren't wifi.)

[colejohnson66]

The same things you'd use GPIO with Linux for on a Raspberry Pi: anything.

[graphe]

Anything is not a useful comment. When? I'm asking for a use case, I haven't seen anyone use them for a specific reason to use Linux. I'm asking about sensors and software that works together better than using it with an MCU

[ianburrell]

One example that I'm working on is GPS receiver and NTP server. Accuracy requires PPS signal through GPIO. It would be possible to wire up GPS receiver board to microcontroller. But still need server to run NTPd. Or could put GPS Hat on Raspberry Pi and have everything in one unit. It will run on the cheapest $35 Pi, or extra one in my case.

Another I have thought doing is ADS-B receiver mounted outside. It helps to put the receiver close to antenna so would put the SDR and Pi in enclosure, and power it from PoE. Microcontroller can't run the SDR. Micro PC is overkill and wouldn't work in enclosure. Doesn't use GPIO pins.

[graphe]

Very interesting, I haven't used gps but that definitely does need more power (or optimizations). Have you heard of this? https://hackerwarehouse.com/product/portapack-h2-for-hackrf-...

Linux would probably be very easy to built without needing firmware

[ssl-3]

I've used GPIO on a Raspberry Pi Zero W to talk with DS18B20 temperature sensors, along with an SDR attached with USB tuning in radio traffic and decoding AX.25 packets in software.

I've also used GPIO on a Raspberry PI Zero W to build a Stratum 1 NTP server with nearly spooky accuracy with the PPS line.

Both things worked very well. They were compact, performant, used an inconsequential amount of power, and were very inexpensive.

And both things were very easy for me to implement, largely due to the tremendous amount of software available in the Linux-ey ecosystem.

If I were trying to bodge an MCU into performing these tasks without involving Linux, I'd probably have never gotten either of them done.

[kllrnohj]

Especially if you're willing to go used. 5 year old lenovo, dell, and hp mini PCs are all over ebay as companies dump them due to simply being out of the typical 5 year enterprise warranty. They are otherwise still very potent and capable machines

[michaelt]

> the big change is that x86 SBCs and mini-PCs have gotten very cheap

Yes - and at the same time, the RPi has gotten more expensive, rising from ~$25 circa 2013 to $60-$80 for the latest RPi 5. Neither price including power supply and SD card. Of course the RPi 5 has more cores, a faster clock speed, more RAM, and built-in wifi so you do get more for your money.

Once upon a time, you were looking at $25 for a Pi and $250 for intel. These days it's more like $80 vs $180.

[ThatPlayer]

The Raspberry Pi 4 is still good value at $35 . If your use case can be handled by a Pi 4, it's a good pick at that price range over the competitors. Most of the competitors are going to have similar i/o, but with a Rockchip RK3566 chip which is slower (unless you're using the NPU)

The Raspberry Pi Zero 2W is also very interesting for the size and $15 price tag. I also liked the 3A but no one remembers that one.

They're older, but everyone else is still playing catch-up, and Raspberry Pi will produce them for a while. I do hope they have a proper $35 board to upgrade to in the future.

[dvdbloc]

Sure if you are trying to get a cheap desktop computer, the Pi always made a mediocre desktop experience. But if you need GPIO or very low power consumption or a SPI connection with a community that understands its quirks very well I doubt you are going to be happy with an old Intel desktop.

[michaelt]

The low power, GPIO and SPI on the Pi are all trash compared to microcontrollers, most of which are also cheaper and better documented.

But if you specifically want to run Linux and have SPI and GPIO on the same chip then sure, the RPi will do that.

[chrisjj]

OOI, why would any user care what's on the same chip?

[michaelt]

Well, often they wouldn't.

In some cases you want to avoid your programmers needing to know two designs, compiler toolchains etc - a microcontroller might push you towards using C, and perhaps all your other code is in Python and you'd prefer to keep everything in Python.

If you're making something like a high precision time server synchronized to GPS, you might want your GPIOs to trigger direct interrupts on the device with the ethernet port. Of course, IIRC the RPi has USB ethernet so it's not a good choice for a truly high precision time server.

[mixmastamyk]

Don't forget the 20-40% inflation over the last decade.

[tombert]

Yeah, it's actually insane how much X86_64 stuff has dropped in price.

Yesterday I received two Ryzen 9 mini gaming computers [1], one to replace my old rack mount server and one to be a home theater PC. Each cost about $400, and they are capable of emulating the PS3 and Xbox 360 smoothly (I don't really have any new games so I wasn't able to push the limit too much, but still emulating those consoles requires some horsepower!).

Maybe I'm just out of the loop (very likely), but $400 for a super low-power gaming computer feels insanely cheap to me. The server one in particular will pay for itself in about a year due to power savings alone compared to my rack mount server.

[1] Beelink SER6's for those interested.