Hacker News new | ask | show | jobs
by randomstring 1918 days ago
"Outside of commercial use, the $100 dollar price tag is a little high for the 'impulse buy then stick it in a drawer' use case most of us using Pis are familiar with."

I swear, some day, maybe even soon, I will find a use for all the Raspberry Pis, various Pi POE adapters, Pi cameras, and sensors I own.

13 comments

I suggest you don't develop an interest in esp32, or like me you may add an equivalent pile of those devices to your gaggle of interesting but unused hardware.

At least it's much cheaper that pi!

I've really gone down that rabbit hole recently, and I get it, but I don't regret it. There's a whole world of electronics that I've been missing. As wonderful as Linux is, at the end of the day, once you have Linux running on a device, it becomes a bit generic. The Raspberry Pi is useful and fun, but they are sort of interchangeable with any other Linux computer. These gumstick-sized microcontrollers bring back some of the joy I had with computing in years past.
Linux is indeed wonderful, but there's a lot to be said for dealing with things at a simple level when your goal is to e.g. measure voltages, turn LEDs and relays on and off etc.

I still find it incredible that a fairly fast, dual core computer with a color display, wifi, bluetooth, USB, battery charging and all the memory you need costs $8! [0]

[0] https://www.aliexpress.com/item/4001235066814.html

That's really an incredible price for a computer with a color display. I enjoy and use Linux, but I think it's so versatile and general purpose my inclination is to put it online, run Firefox, play videos or whatever, and then it's magically just another PC. It's kind of like the old saw about every program expanding until it can do email. I'm starting to see the small devices, like esp32 inherit some of the aura of the old home computers which ran BASIC from ROM.
Not sure if you were referencing gumstix there, but I remember fantasizing about getting one of the tiny SBCs over a decade ago but they were too expensive.

https://en.wikipedia.org/wiki/Gumstix#/media/File:Gumstix_oc...

A decade later we have ESP32 and RPi Zero. And it looks like gumstix have read the writing on the wall and now make RPi accessories.

https://www.gumstix.com/

I don't think I was consciously referencing Gumstix, but that must be where I first heard the term. I remember being interested in those at the time, but like you I thought they were too much.
From ESP there’s downsizing to 555timer chips

https://howtomechatronics.com/how-it-works/electronics/555-t...

microcontrollers are cheaper than 555s these days
The thing that I want in the future is things at the ESP32 price point that can actually do interesting work - i.e. 1GSPS ADC and an FPGA on a board for 20 bucks let's say.

I suspect moore's law may have died too early for it, but I can dream...

Don’t forget the need compare different esp32s or esp8266s.
I have redundant pi holes and NTP servers running. One of them is GPS/PPS trained with chrony for some truly accurate network time.

I have another pi with a SCART hat and 180 GB of ROMs driving my BVM.

I have a 0w modulating its clock with Daftendirekt at 7am every morning for a pirate FM radio alarm clock.

If I had more impulse purchasing power I’m sure I would like to experiment with octoprint on my CR10S-Pro.

There are lots of things you can do with Pis. My use cases are far from the most fun or clever. You just have match them to your interests :)

To be fair, I have 7 Pis running on my network. Home Assistant, 2x Pi-Holes (for redundancy), 1 magic mirror, my Weasleyclock, 1x w/ a hi-fi berry acting as a Spotify streaming device, and a garage door sensor. So roughly half the pis are in service. Maybe only 5% of all the sensors and projects are.
I have a rpi 2b with a hifi berry DAC hat too. It works great. It is attached to a timecapsule with 20cm ethernet and usb cables, for data, network and power. Nothing important on the sd card.
How do you set up the pi holes for redundancy? Just manually configured as primary and secondary DNS, or some nifty configuration syncing?
Both. Have your router (optionally all clients) point to each DNS server. You can go further by keeping the pi holes synchronized:

https://github.com/vmstan/gravity-sync

Since some hostile clients (such as TVs) have hard coded DNS, it is necessary to forward all port 53 and 853 traffic to a pi hole. This is easy enough with NAT redirection rules in the router, even with two pis.

https://www.myhelpfulguides.com/2018/07/30/redirect-hard-cod...

Not your parent poster, but I manually configured them as primary and secondary DNS servers (dockerized PiHole), and then just used pi-hole's "export configuration / restore configuration" tool to keep the DNSs mostly in sync.

I heard there's a tool called Gravity Sync that will sync them, but I have not tried it yet.

Techno Tim on the topic https://www.youtube.com/watch?v=IFVYe3riDRA

https://github.com/vmstan/gravity-sync

I just advertise both Pi-Holes via DHCP and when I configure manual DNS settings. The primary DNS gets the vast majority of the DNS traffic, about 150 requests/minute and the secondary gets about 10 requests/minute (mostly from a single device).

Both piholes are on different UPS power, different switches, in different locations. In theory the lights will go out on the main UPS and switch first (it draws more power), but this configuration did save me once.

My guess would be for guest/home use or maybe for different devices/profiles.
The typical reason for running redundant pi holes is high availability. If you really want all DNS traffic to go through your filter then your internet ceases working as long as your DNS server stops running.
If you have an extra Pi Zero W, Klipper has lower system requirements than Octoprint and runs better if you don't need any of the plugins that Octoprint offers, or a USB webcam hooked up.

Though it will involve flashing Klipper over Marlin on the CR10. That just means more stuff to tinker with!

Daftendirekt - the Daft Punk track? By "modulating its clock" do you mean playing the song as an alarm?
Sorry, I meant "Homework" as in the entire album.

By "modulating the clock" I mean modulating the SoC base clock frequency (nominally 100 MHz, but increased to be a valid and unused FM channel, if decreased then the pi locks up) with the audio to make an FM transmitter. Hook up a wire to the clock output GPIO pin and you have an FM antenna. Lay it next to an old FM clock radio and you now have a clock radio that plays whatever you want. Make a cron job and forget it.

https://github.com/pimylifeup/fm_transmitter

That is pretty cool. I'm actually working on a Raspberry Pi based clock and now I want to incorporate this somehow. Thanks for sharing.
I’m certain it plays hell on software timekeeping. If you don’t have an RTC then switching to chrony and increasing the poll rate should help prevent potential clock error.
The tipping point for me was setting up the infrastructure to network boot my Pis. Now it's trivial for me to plug in a Pi anywhere on the LAN, and even switch what OS it is booting into just by changing a symlink on my fileserver. It's now very easy to experiment with different things, and not worry about the cards dying.
This has been on my TODO list for a while. But first I need to set up another Pi to be the PXE server... :)
It doesn't need to be another Pi, of course.
Recommended howto?
Googling Raspberry Pi Network Boot will return the official documentation - it's a built in feature of the Pi boot rom.
I think the answer for those projects is probably a netboot diskless pi and have a server that handles the PXE boot + disk.

Folks here have done it, then all your pis are online easily, especially with poe.

I think it would be great for camera stuff - it's like VMs turned inside out where your server runs lots of remote physical machines.

Hah! As I look down near my feet there is a clear plastic bin full of pi's, usb cables, micro hdmi, a picam, a go pro, all kinds of crap I swear I will use and never do.

I do have a pihole running on a pi3 that has been serving dns for my home network for about two years now without so much as a hiccup.

I usually use them as local dev env. I deploy everything to my local cluster before I try to run it on a real infra. It is pretty good. I can also virtualize some of the workload using Firecracker.

https://dev.l1x.be/posts/2020/11/22/getting-started-with-fir...

This seems like a great use case. I have a refurbished 1U server I use, but the fans on that thing are sooo loud.
There's a price point here that makes sense, and it isn't $100 + the Pi + the M2 SSD. Anything more than this and you get into the low-end laptop price range with full x64 compatibility and a Windows license.
Except by that point you're dealing with a full laptop with proprietary drivers and, well, Windows itself.

There's a reason a Pi took off as the SBC of choice: How open it is and what it still can do without adding things to it.

If you're only looking at price tag when it comes to adding an SSD and a hat to compute module, the compute module concept was never for you in the first place.

I have three Raspberry Pi computers. The third, a Pi Zero came in the mail today. So I'm sold on the strong points of the system.

My point wasn't about the laptop having Windows, just that there was a "Windows tax" on the inexpensive laptop and it still offered a better price / performance value. I bought a laptop a couple of years ago for $250. It has a display, two kinds of USB ports, HDMI, Ethernet, a keyboard, trackpad and a battery. I'm sure I could run Linux on it if I needed to. It's not fast, but it's faster than any tricked out Raspberry Pi.

If we envision the Raspberry Pi as a learning tool, it's almost too good. It's really too powerful and too complex. As a general purpose computer it still falls short of what I consider a good use of my free time. Don't get me wrong, it's fantastic that there is such a wide market for add-ons for the Pi, for an aftermarket of small players with neat ideas. I have to pry myself away from the sites where they sell this stuff. But this project is just a little too expensive to make it worthwhile for me. I'd like to see a Pi+M2 kit for $100, which likely there will be in time.

For lots of low income people Linux on ARM is a down grade and the stuff that only "desperately poor" people would even consider. Having a "proper" laptop with a "proper" OS will decrease the perceived difference between yourself and other non poor people.
I’m experimenting with self-hosting platforms, like sandstorm.io. (It is not currently available on an rpi, though there is a lot of interest within the community)

Right now though, going to setup pi-hole so my daughter can stay on task during remote learning, and if we ever get a smart TV, pi-hole the adtech dns.

This comment, and the general response to it, made me feel slightly less ashamed. Thanks for that! =)
I recently had a need for one (installation of Octoprint), but then realized the one I had in a drawer was too old to work. So I ended up having to purchase a new one anyways.
Just put LibreElec on the Raspberry Pi 4 and you instantly have a cheap media player capable of running HEVC video.
I use my pis to run an air quality sensor. It runs continuously.
Develop a remote temperature monitor (freeze alarm).