Raspberry Pi: yeah we're pretty much all on desktops again

peepsalot · # ¿ May 9, 2013 22:19

A simple optointerrupter would make more sense than an actual motion sensor, unless that's what you meant to say.

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peepsalot · # ¿ May 11, 2013 06:03

The Automator posted:

The machine has to have a user interface. It has to include a card swiping mechanism, and it has to give the student money. I couldn't think of a better way for it to give out money than to have a couple bills in a tray that has a door in front of it. I mean, if its easy to spit out cash into a tray, I'm all ears, but I think a small sliding door to reveal cash would be easier.

I can rig up something visually close enough to a card reader to work. I've looked at card readers online and they run about $50 at the lowest end compared to under $10 for a motion sensor.

Get some old scrap lovely bubblejet or whatever printer and just have it page feed a bill at a time like a real atm.

peepsalot · # ¿ May 23, 2013 22:13

Looks like some sweet progress being made on wayland/weston on rpi :woop:

http://fooishbar.org/tell-me-about/wayland-on-raspberry-pi/

Will this make rpi almost usable as a general GUI desktop box?

peepsalot · # ¿ Oct 7, 2013 20:06

TVarmy posted:

Why not a class 10 SD card? They're fast and not that pricey. Here's one for $12 at 16gb.

I could be wrong, but I remember hearing that usb transfers occupy the CPU quite a bit.

Actually I don't know the details, but I thought I remembered people bitching about the opposite, that the sdcard on the pi is on the same bus as some other poo poo and basically is slow as balls compared to anything else.

e: A link. http://www.raspberrypi.org/phpBB3/viewtopic.php?f=2&t=5057

I haven't read through the whole thread yet to see if anything was eventually figured out, if its possible to solve in sofwtare or its a hardware limitation, but the gist is that a sd card reader over USB is faster than the builtin sdcard port(at least in April 2012 that was the case).

peepsalot fucked around with this message at 20:13 on Oct 7, 2013

peepsalot · # ¿ Oct 26, 2013 01:10

I like turtles posted:

I want to build a wifi enabled meat thermometer based on a raspberry pi. I have zero practical experience with electronics.
How do I get the board hooked up to one of these? http://www.amazon.com/Polder-Replacement-Oven-Probe-THM-362-86/dp/B002GUJ82I (or any comparable thermocouple with a solid probe like that)
I'm certain I can figure out the rest as I'm a big fan of Python, but the hardware interface is what's get me stuck.

Looks like a standard 1/8" 2 conductor(mono) plug, just get a jack for one.

You could get something for it on mouser or probably a billion other places. Or salvage one from some junk audio equipment.
http://www.mouser.com/Connectors/Audio-Video-Connectors/Phone-Connectors/_/N-778cv?P=1yzrwr8Z1z0wxp0Z1yzv8y5

It could be in another size that is not quite 1/8" though, maybe 2.5mm which you can also find jacks for.

Also you're going to need some kind of amp for that thermocouple if you don't already have one. They output in the millivolt range. I haven't messed with ADCs on the pi, but I'm assuming they read in something like 0-5V range.

Edit: poo poo I guess pi doesn't actually have any built in ADC. Get a chip made to convert the thermocouple millivolts into digital
http://www.maximintegrated.com/datasheet/index.mvp/id/3149
here is a board with the chip on it that might be handy http://www.digikey.com/product-detail/en/MOD-TC/1188-1028-ND/3471434?WT.mc_id=PLA_3471434
You can then communicate with that chip via SPI pins on the pi.

I'm also under the assumption that that is a K-Type thermocouple(most common kind), since I didn't see it specify on the Amazon description. If its not then that chip is gonna give the wrong readings.

peepsalot fucked around with this message at 01:21 on Oct 26, 2013

peepsalot · # ¿ Dec 13, 2013 23:44

Are there any pi-like low cost boards out there now with a bit more CPU/RAM suitable for GUI desktop stuff. Beaglebone black? Anything else? Looking for a nice little embedded box for a simple public web browser terminal. Seems the pi really struggles on this sort of thing.

peepsalot fucked around with this message at 23:59 on Dec 13, 2013

peepsalot · # ¿ Feb 2, 2014 02:26

You could try berryboot http://www.berryterminal.com/doku.php/berryboot

I haven't tried it yet but it claims to support CEC so you can use your TV remote to select what to boot, which is pretty handy.

peepsalot · # ¿ Apr 25, 2014 21:07

keyvin posted:

"Now you real can do your daily works on it"

If they can't put together a coherent web page, How can they put together a reliable board?

Edit:
Adafruit had some beagle bone blacks in stock and mine comes today. Looking forward to playing with the thing. I also ordered an 8 channel (is that the right word?) level shifter I need to solder together. Looking forward to interfacing with my arduino.

I can't speak to the quality of the board, but I don't think being a fluent english speaker has any bearing on PCB design.

peepsalot · # ¿ Apr 28, 2014 20:51

ante posted:

I was actually just thinking last night that I really need an IR sensor for home theatre Pi.

Are you sure you can't just use your TV remote? libCEC worked great for me out of the box with raspbmc and openelec.

peepsalot · # ¿ May 6, 2014 20:28

Yeah just don't use OpenElec if you are planning on installing extra packages from a repo. raspbmc should be fine

peepsalot · # ¿ Jan 20, 2015 23:01

JazzmasterCurious posted:

Apple ... interoperable

lol

peepsalot · # ¿ Apr 15, 2015 22:32

Are there any pi-alike boards with built in wifi that are cheaper than buying pi and wifi dongle separately?

peepsalot · # ¿ Jan 29, 2016 05:52

BattleMaster posted:

Edit: The real problem is finding a wall wart that can output 16 amps at 5 VDC, lol

Not a wall wart but you can easily get 5V 20A power suppplies for about $15-20
Hell you can even get 5V 60A for a few bucks more. here for example: http://www.ebay.com/itm/301685560616

peepsalot · # ¿ Mar 10, 2016 20:02

Does anyone know how the RPi3 performance compares with the Pine64, on paper at least?

peepsalot · # ¿ Mar 3, 2017 21:20

Judge Ito Boxing posted:

Recently I ordered two Raspberry Pi 3s a few days apart from the same Amazon link. One arrived in a secure, official-looking box, while the other was shipped loose in an anti-static bag housed in a bubble wrap mailer.
The one that came in the bubble wrap is missing a GPIO pin.

It hasn't been sheared or bent off or appear to have been damaged in shipping. It looks like it was never there at all, kind of like what happened to the guy at this link. I was never planning to use the GPIO pins on either of these boards, but I'd like to know if it's safe to use this one at all. Like, is it going to short out or burn anything down if I plan to use it as a 24/7 pihole/vpn box? FWIW, if I'm reading this layout right, it's pin #38 GPIO20.

I'm of the opinion that it is perfectly safe to use and would not be worth the hassle of returning and waiting for a replacement, personally. It appears that the pin was missing from the header before it was put on the board. What does that pin look like on the back of the board? You should be able to tell if a pin was there or not when the board was wave soldered or whatever.

If you ever handle those 0.1" headers like that (before they are fixed to a board), the pins can slide in and out of the plastic brace with a little bit of force, so its not completely unheard of for one to come loose.

peepsalot · # ¿ Jul 4, 2017 00:33

Are there any sites that aim to benchmark the various *-Pi devices, Beaglebone, et al?

Would be neat to see how they stack up for various things, like storage I/O throughput, network bandwidth, compute, graphics, etc.

peepsalot · # ¿ Oct 7, 2017 17:54

LochNessMonster posted:

what would be a good place to start reading on how to get an (ancient) arduino (mega 1280) working?

I ordered one 7-8 years ago and never used it. I tried to hook it up to my laptop this but I can't push any stuff to it. Getting some error messages that are occuring often according to google but the solutions for other folks don't seem to do the trick for me.

cool error messages bro

also there's an arduino thread, since microcontrollers are pretty different from pi-likes.
https://forums.somethingawful.com/showthread.php?threadid=3505424

peepsalot · # ¿ Nov 7, 2017 03:19

I want to play around with "high-speed" computer vision on a Pi3 or pi-like. I'm mainly wondering what the highest fps i can get (even if it is really low res). I see, for example some 2MP usb camera modules on ebay for $40 or so that claim to be capable of 120fps at lowered resolutions like 320x240.

Another option could be a mouse optical flow sensor, i know some are used to aid with quadcopter position holding, and have resolution of 30x30 for the common ADNS3080 chip. As I understand it, these chips process tens of thousands of frames a second for calculating flow data, but actually grabbing a frame off the chip is much slower, ~100fps tops if my rough calculation is correct, probably a lot less in practice?

So any particular recommendations for camera modules, and/or system to run them? With a total budget of ~$100 for computer + camera.

peepsalot · # ¿ Jan 29, 2018 00:48

These waveshare e-paper modules are available to buy:
https://www.waveshare.com/product/modules/oleds-lcds/e-paper.htm

They have a bunch of different sizes and some even have three colors: black, white, and red!

I picked up a 2.9" three-color module from ebay a little while ago, but haven't gotten around to implementing anything with it yet.

You can find various videos on youtube showing how to use them:
https://www.youtube.com/watch?v=OPaCF-XJhqc

peepsalot · # ¿ Feb 3, 2018 19:04

Dht11 is a really common temp/humidity sensor in one

https://learn.adafruit.com/dht/overview

peepsalot · # ¿ Mar 24, 2018 16:43

xzzy posted:

I'll have you know I've fixed way more stuff with a soldering iron than broken it!

Granted an actual electrician would poo-poo everything because the results look like poo poo, but stuff works.

I could be wrong, but I'm pretty sure real electricians don't actually have much use for soldering irons. The wires in your house are (hopefully) not soldered connections.

peepsalot · # ¿ Mar 24, 2018 19:13

xzzy posted:

I just use that for brevity, gently caress if I'm gonna type out "electrical engineer" every time it comes up.

"EE" works :shrug:

peepsalot · # ¿ Mar 24, 2018 20:57

The TS100 is a very capable iron and I'm quite impressed at the compactness of it all, with the caveat being that it needs an external battery or power supply.

One of my favorite things about it is that the firmware is reflashable with alternative open source firmwares (not sure if the stock firmware itself is open). I just like supporting product design that is hacker friendly enough to make reprogramming with custom firmware possible, which is rare for a lot of modern electronics aside from networking routers and android devices.

peepsalot · # ¿ Mar 24, 2018 21:14

alnilam posted:

Not if your soldering iron is cheap and sucks rear end i have to hold the tip in place for like 10-15 seconds before the solder melts. And I don't think it's just me, as I've had better luck with the good iron in my lab.

Do you clean and wet the tip? I little bit of already liquid solder on the tip really helps provide a good heat conduction surface area as oppososed to what would otherwide be a single miniscule point of contact.

Its also possible that the tip needs replacing if solder does not wet it easily.

And if its not temperature regulated throw it in the trash and stop torturing yourself.

peepsalot · # ¿ Mar 24, 2018 21:57

I've watched this old school soldering series in the past and found it pretty interesting and informative, although a few of the sections cover terminal types that are basically obsolete, still helpful to see how the various shapes take solder etc.
https://www.youtube.com/watch?v=vIT4ra6Mo0s

peepsalot · # ¿ Sep 27, 2018 05:27

pairofdimes posted:

Regarding the randomly corrupting SD cards, I saw a video from a Linux conference where the speaker mentions finding a bug in the generic SD infrastructure where probes to detect if the card was present could occur during a read or write and corrupt it. That would explain why the corruption seemed really random since it actually was.

This is the video, it should start at the relevant time (30:43): https://www.youtube.com/watch?v=o0milqmt4ao&t=1843s

Is this polling corruption thing confirmed/still an issue on RPis?

peepsalot · # ¿ Jul 25, 2019 00:50

I just became aware of RISC-V recently and was curious what sort of options are out there currently, which led me to this interesting system:
https://www.seeedstudio.com/Sipeed-MAix-BiT-for-RISC-V-AI-IoT-p-2872.html

64bit dual core RISC-V @ 400Mhz with FPU (single & double precision), overclockable to 800Mhz
Also has a KPU(analogous to a tensor core i guess?), and a bunch of other neat stuff.
Seems to be specifically aimed at IoT machine learning type tasks and computer vision, but could be handy for as a super cheap general alternative to rpi/arm with reasonable computing power(for the cost anyways).

There is an even a cheaper ~$8 module/breakout thing or $9 with wifi.

Here's one play Quake 1 @ close to 60fps
https://www.youtube.com/watch?v=poBBrIWt_HE

peepsalot · # ¿ Jul 25, 2019 05:19

mewse posted:

Is that the 320x200 software renderer?? Like 1996 pentium speeds?

Dude, I don't know, just thought it was neat. It is $12 for a full dev board...
Of course its only 400Mhz so its not quite in the same league as higher end multi Ghz ARM chips, sorry to bring up such a lovely dumb thing.

peepsalot · # ¿ Jul 25, 2019 06:53

General_Failure posted:

It can run quake? Is there a binary for that? The camera and TFT arrived for my Grove AI HAT yesterday (same K210). Haven't had a chance to try them yet.

https://github.com/elect-gombe/quake-k210

Found the link from here, bunch of other demos too (incl Doom)
https://maixduino.sipeed.com/en/others/what_maix_do.html

peepsalot · # ¿ Oct 8, 2019 00:43

I picked up a couple raspberry pi 4 (2GB and 4GB) the other day to play around with. Anyone messed with 64bit OS on these? I searched around a bit and it seems there are maybe a couple options out there, with Manjaro probably being the best of them?

I put an image on sd card but it looks like they don't support headless setup, so I had to order some new micro-HDMI cables. I accidentally ordered some mini-HDMI cables then realized my mistake a few hours later. Amazon says the order is already about to ship, so not guaranteed it can be cancelled in time. I guess I'll see in a day or two. :sigh:

peepsalot · # ¿ Oct 8, 2019 01:23

mystes posted:

What do you mean "it looks like they don't support headless setup"?

Well I was searching for info on the default SSH login etc and if it was enabled by default(on raspbian for ex. you have to put an empty "ssh" file on the root folder of the boot partition to enable it) and I came to this post that says the installer needs display attached|:
https://forum.manjaro.org/t/solved-cant-login-via-ssh-on-brand-new-arm-installation-raspberry/93026/4

I mean the post is a few months old so maybe things have changed since then? Do you know any different?

Also to be fair the 2nd part of that post mentions a way to maybe make it work(my ADD brain skipped over that the first time), not sure if it really works, haven't tried it yet.

peepsalot · # ¿ Oct 14, 2019 22:55

mod sassinator posted:

Yeah if you're just starting with Pi's... don't use Manjaro or other alternative distros. Get used to plain old Raspbian first. And there's really no benefit to 64 bit OS on the Pi--at most you've got 4GB of RAM anyways so you're just wasting memory with bigger pointers, etc.

This is my first time playing with a Pi 4, but I've messed around with probably close to a dozen Pi or other SBCs over the years.

My post was mostly just me being salty about the need for yet more cables/adapters all because they wanted the dubious utility of dual monitors on a RPi.

I would actually be very interested to see something like a poll of RPi 4 owners: "How many displays do you use with your Pi: [0,1,2]".
I have a feeling 0 would be the majority or at least plurality of responses. While I can't imagine votes for 2 would be more than 5%.

Anyways, my mirco-HDMI adapter came in and I installed Manjaro successfully, which feels fairly snappy and good overall. I used it to build and benchmark some C++ code I'm working on, so everything worked out. Installed both gcc and clang no problem and built my code on the unit itself.

I haven't tried comparing against 32-bit OS yet, but I kinda assumed that it would perform poorly for my specific application which is doing a lot of large integer math. I guess I'm still not really clear about if 32-bit OS means that 64-bit instructions are then off-limits? Like can you still compile for 64-bit integer arithmetic operations or does it end up decomposing them into multiple 32-bit instructions?

peepsalot · # ¿ Oct 21, 2019 19:38

ItBreathes posted:

I'm just looking to do light word-processing, nothing but text. The original idea was to repurpose the screen of a dead phone but Google made it seem like that was a no-go. Someone above mentioned networking a phone to the Pi directly which should satisfy my needs, though I haven't tried it yet.

I would think you'd be better off just getting a cheap tablet. And like, a bluetooth keyboard or something.

peepsalot · # ¿ Oct 23, 2019 01:12

ickna posted:

Definitely this. A FireTV 4K with Kodi installed will let you play anything off your network storage and still do Netflix, Hulu and Prime with the least amount of friction.

Can it play Youtube videos at alternate (1.5x, 2x etc) speeds? None of the youtube tv based apps I've used seem to allow it.

Also does the alexa remote record you at all times and send your life audio to Senor Bezos? :tinfoil:

peepsalot · # ¿ Oct 24, 2019 04:47

MikeJF posted:

Picked up a Pi 4. Heard if I want to do much heavy with it I'll need decent active cooling? What's a good cheap neat tidy little casing for it, anything in particular?

I don't have any specific case recommendation, but just to give an idea of the amount of cooling needed:
I put a basic tiny GPU RAM heatsink on my Pi 4, barely larger than the CPU package, just attached with heatsink tape, passively cooled.
I was running it open air, no case, basically just sitting on a coffee table. I ran a process for days on end on all 4 threads, 100% load and it didn't get above 62C or throttle. I wasn't overclocking though.
I would say it depends what kind of "heavy" work you plan to do with it. Will you really be continuously loading the processor?

But yeah I would just look for something with decent ventilation esp. if you go the passive cooling route. Of course a little fan would help even more but you might not necessarily need it.

peepsalot · # ¿ Oct 25, 2019 02:32

mod sassinator posted:

Fire TVs have the android youtube app now, so if it works on android it should work on Fire TV.

So I ended up getting one.

Based on the fact that I can watch different speeds on my phone or tablet, you would think that the Youtube app for FireTV would do the same, but no it still wasn't possible through the default Youtube app. Youtube seems to cripple all TV-specific versions of their app.

However I managed to sideload "Smart Youtube TV" and which works well and allows speed settings. Also just a note that t was dropping like 25-30% of frames on the (default?) "avc" codec, but doesn't drop any after swtiching to "vp9". (my tv is 1080p only, didn't try decoding 4k at speed).
So I'm pretty happy with it now.
Also I was pleasantly surprised that the remote volume controls work with my audio receiver, since I don't run audio straight from tv speakers (couldn't ever get Roku to do that, it assumes TV is the only possible sound control afaict).

peepsalot · # ¿ Oct 25, 2019 02:46

Progressive JPEG posted:

I went with small heatsinks* on each rasppi paired with a 140mm fan blowing across each 4x stack of them. IIRC they maxed out around 55C even with overclock (over_voltage=2, arm_freq=1750). Could�ve probably just gone with 120mm fans for a more standard size.

Back to being on topic: Just curious how many total you have, and is there a vendor that sold them to you in bulk? All the online stores I've seen have a "limit 1 per customer" per rpi 4 model.

I was thinking about making a cluster of a few of them, but didn't want to make a bunch of single orders and pay inidividual shipping etc.

peepsalot · # ¿ Oct 27, 2019 01:10

Shinjobi posted:

I think I finally found an excuse to buy myself a pi. Got an old TV in the bedroom not connected to anything; pretty much used primarily for blu-ray/dvd stuff. Apparently you can use a pi for Kodi-enabled PS Vue? If I were to try to set that up, would anyone familiar know the best way to control the system? I'm not opposed to using a bluetooth mouse if need be, but I'd be lying if I wasn't curious to see if there were any remote controls for Kodi stuff.

Unless the TV is *really* old, it should be possibel to control Kodi via the TV's native remote:
https://kodi.wiki/view/CEC

Adbot · # ¿ May 12, 2024 06:48

peepsalot · # ¿ Oct 30, 2019 20:16

Combat Pretzel posted:

I found this heatsink for the Pi4 on Amazon, works pretty nicely.

drat that heatsink is sick. What's the price on that?

Combat Pretzel posted:

The thermal pads that ship with it, the CPU one is too thick. They're all 1mm, whereas the CPU needs 0.5mm. It still gets pretty warm, heh.

So are you saying that with the stock pads, the CPU contacts the heatsink, but not the other chips?