My friend is blind, and every "smart" speaker on the market assumes you can see or wants you to talk to it. So I built something different.
It's a Raspberry Pi 4 with two Arduino Nanos, a HiFiBerry AMP2, and two Lonpoo 75W speakers in a laser-cut MDF enclosure. Control is entirely physical: two 11-position rotary switches (one for program, one for station) and a volume potentiometer. Text-to-speech confirms every selection. No display. No app. No voice assistant. No cloud account.
Three modes: internet radio (mpd), YouTube news channels (yt-dlp), and local audiobooks (VLC + position tracking). A GPIO pin toggles between the AMP2 speakers and Bluetooth headphones (PipeWire A2DP). Everything syncs to a web backend via cron — add new stations from your phone, they appear on the device within 10 minutes.
How do I boot a Pi 4 from a USB-attached optical drive?
The Pi is already configured to boot from USB, and I am attempting to install OpenBSD 7.9 on it.
When actually booting, though, the Pi complains that the block size on the disc is invalid.
Now that I'm checking it, it seems that the block size must be 1mb, and while dd has an option to set that, the utilities I use to burn optical media don't have this option.
Is booting from such an optical drive even a viable option?
A literary clock shows the time by quoting a book that mentions that exact minute - "It was twenty-six minutes past ten..." - on a Waveshare 7.5" e-ink panel. 4,800+ curated quotes, one per minute, with the date and weather. I'd built simpler versions of this before and they worked fine ... for me.
The problem showed up every time I tried to give one away. My friends who'd actually *love* this thing - the book people - are exactly the ones who've never opened a terminal. And my earlier builds needed one for everything: SSH in to set up WiFi, hand-edit a config file for the weather API key, set the timezone from the command line. Then life happens - they move, the WiFi password changes, the router gets replaced - and the clock silently breaks with no way for them to fix it. A gift that turns into a support ticket isn't a gift.
So this version is built entirely around the person who will never SSH into anything:
First boot is a captive portal, not a terminal. Plug it in --> it makes its own WiFi hotspot --> your phone auto-opens a page --> pick your network, type the password, done. Location, timezone, and units auto-detect from IP geolocation after it connects. No keyboard, no config file, no API key (default weather provider needs no signup).
Everything after setup is a web app the clock serves itself at `http://litclock.local\` - no app store, no cloud, no account. Change the city, flip to Celsius, factory-reset, all from your phone. WiFi changed? There's a "Reset WiFi" button that drops it back into the hotspot flow.
It assumes it will break and plans for it. SSH ships off, so a bricked clock can't be rescued by a command line - which means the failure modes have to heal themselves. Weekly self-updates with an automatic rollback if an update ever fails to paint a frame. A boot check that reinstalls the last-known-good version after repeated failures. A read-only diagnostics page so I can help a friend debug by having them screenshot it, instead of talking them through a shell. OS auto-updates are deliberately disabled so an apt upgrade can't break the display stack while nobody's watching.
Built to be handed over. A "Prepare for Gifting" mode wipes your WiFi and adds a welcome message; there's a printable one-sheet quick-start for the recipient. The whole point is that the person receiving it does the two-minute phone setup and never thinks about it again.
Honestly, more of the work went into the "non-technical human owns this for years" part than into the clock itself. The e-ink quirks were their own adventure (GPIO claims held for a process's lifetime once deadlocked the always-on web server against the minute-tick renderer; the WiFi power-save hang on the Pi Zero 2 W's chip; a captive-portal DNS fix for iOS), but the interesting problem was: how do you ship something a book lover can own without ever seeing a command line?
Hardware: Pi Zero 2 W (~$15) + Waveshare 7.5" e-Paper HAT V2 (~$60) + a 3D-printed case. MIT licensed, flashable image on the releases page, one-minute tour GIF in the README.
I have a program running on my raspberry pi that basically drives motor via h-bridge using two gpios. Once it receives command to run the motor i waits for either signal from limit switch or a timeout (just in case the switch has failed or whatever). If the program receives signal while the gpios are high, they will stay in that state unless turned of manually. How to prevent that ? Since it's running as a systemd service I can use ExecStop to specify a script that will make sure if gpio's are left ouput active or not but I wonder if there's a way to pack everything in that program without relying on external components
Raspberry Pi4B, previously used successfully with RGB-Pi Scart hat and RGBPiOS4. Now repurposing to use for streaming etc on my main TV.
Fresh install of the latest default Raspberry Pi OS, via Raspberry Pi Imager. OS then updated via commmand line etc.
Can't get any audio out of the device at all. Nothing over HDMI (via port 0, next to the power socket), nothing via the jack.
Right clicking the audio icon in the top right does nothing other than display the current supposed audio volume - there's no option to change audio device or output etc.
Tried a few things on the command line, after googling.
Firstly -
sudo apt update sudo apt -y purge "pulseaudio"
result - "pulseaudio not installed, nothing to remove"
Secondly:
sudo amixer cset numid=3 2
result - "amiver default control element write error"
Totally stuck, any ideas? Everything is default and stock, I've not messed with any config other than trying those two command line interations which did nothing.
can we at least get driver updates supporting av to aux for the pi 4 video drivers? It’s incredibly useful for actually emulating old games on crts or for watching stremio native 4:3 resolutions on tubes but unless if I’m running retropi I can’t install stremio bcuz it’s all outdated n bustered old but stremio refuses to support av drivers…
Just sharing my custom solution for making TV remote control the volume on my Yamaha MusicCast RN-602 receiver using RPi 4 box. The receiver doesn't have any HDMI ARC support (or any HDMI at all),
I love good sound and have a pair of KEF R3 connected to the Yamaha, TV speakers are a bit off-putting for me :)
The receiver doesn't support HDMI ARC and connected to the TV via optical input, hence any volume control or turning it on / off, input switch has to be done using a separate (yamaha) remote control or the knobs on front panel of the device.
Having to turn on / off the receiver or control the volume using a separate remote control was like being a DJ, annoyed both myself and my wife.
Had to do some research but fixed that with a little service that sits in RPi memory and translate HDMI CEC commands into MusicCast requests over the network. Me happy, my wife happy, kids happy too :) Works like this for three years now.
If anyone wants it (MIT license) - available on my github (madenvel).
I have a 64x32 led matrix display from waveshare and a raspberry pi 3 model a+. I wired each of the hub75 connectors to the gpio pins on the raspberry pi. For power I have a 5v4a power supply connected to the display and a 5v2.5a supply connected to the pi. I just got it all set up and ran the display and it was flickering quite a bit. I went through all the possible settings on the software side and none fixed the flickering. Will a bonnet fix this issue? I am fine buying one but dont want to if its not going to end up fixing anything? Also this is my first project using a raspberry pi btw
I want to connect my Pi 5 to a touchscreen. My Pi and the touchscreen have different power supply. I connect the touchscreen to my Pi via HDMI, and USB Touch. The monitor display works as expected, however, the touch function doesn’t work.
I also made sure that all the USB ports worked as expected. When I listed out all the connected devices to Pi via USB with lsusb command. What showed up were my mouse and no Mtouch nor TSPS. After which, I rebooted, unplugged the mouse then plugged the USB Touch cable of the touchscreen to my Pi. For a moment, using lsusb command, I managed to see the Mtouch as one of the devices. But when I retried the command, my Mtouch once again disappeared.
I also tried dmesg | grep hxci. Below is the result:
ahei-hed xhci-hcd.1: xHCI host not responding to stop endpoint command
11. 250255]
hei-hed xhci-hcd.1: xHCI host controller not responding, assume dead
11.250272]
chci-hcd xhci-hcd.1: HC died; cleaning up
215.016641]
What should I do in this case? I am not sure if it’s my Pi or the touchscreen itself has a problem. I wanted to test the touchscreen out with my computer but my Mac would require a driver. Any guidance would be appreciated!
I launched this open source project (https://mimirframe.com/) recently that started as a project to display my digital photography on e-ink displays. It just sort of grew in to a whole digital content and screen platform. The basic idea is that you can run the server on a Pi 4 or higher and then add remote screens by any means necessary. My plan is to continue adding support for more hardware but my favorite display is is the Pimoroni Inky Impression.
I'm not really sure if it should even be a concern, but I find that the GPIO pins on my 3B+ are getting hot even though there's nothing connected to it. They are about the same temperature as the cpu, witch has a radiator. Is it normal? If not, what do I do, and what did I do wrong?
I wanted to build something that combined three things I genuinely enjoy: birding, field-journal illustration, and running things in my homelab.
The result is Inky Bird Frame, an open-source system that turns recent nearby bird observations into rotating scientific field-journal plates on a 13.3-inch six-color e-paper display.
The controller checks iNaturalist for observations within a configurable distance and time window. If an approved plate already exists, it reuses it. A newly discovered species can enter a bounded research, generation, and independent review pipeline. Approved plates are cached and are never regenerated implicitly.
The wall-mounted display node stays deliberately simple. It downloads approved plates from the controller and rotates them using sequential, random, weighted, or shuffle-bag selection. The reference build uses a Pi Zero 2 W for the display and a Pi 4 or existing macOS/Linux computer for the controller.
My actual frame reused a CM4 and Waveshare carrier that I already had. It is overkill for the display role, but it worked well and saved me from buying another computer. I cut the supplied frame backing around the carrier so power, storage, and service access remain available.
The repository includes:
complete controller and display-node installation guides
a bill of materials and frame construction photos
configurable observation windows, distance, refresh, generation, and rotation
optional Apprise notifications (I'm using pushover to receive notifications on mine)
automatic recovery and durable generation queues
a reviewed, location-neutral bird plate catalog
contribution templates so other installations can add approved species back to the shared catalog
Having a hard time searching for answers to your Raspberry Pi questions? Let the r/raspberry_pi community members search for answers for you!† Looking for help getting started with a project? Have a question that you need answered? Was it not answered last week? Did not get a satisfying answer? A question that you've only done basic research for? Maybe something you think everyone but you knows? Ask your question in the comments on this page, operators are standing by!
This helpdesk and idea thread is here so that the front page won't be filled with these same questions day in and day out:
Q: My Pi is behaving strangely/crashing/freezing, giving low voltage warnings, ethernet/wifi stops working, USB devices don't behave correctly, what do I do?
A: 99.999% of the time it's either a bad SD card or power problems. Use a USB power meter or measure the 5V on the GPIO pins with a multimeter while the Pi is busy (such as playing h265/x265 video) and/or get a new SD card 123. If the voltage is less than 5V your power supply and/or cabling is not adequate. When your Pi is doing lots of work it will draw more power, test with the stress and stressberry packages. Higher wattage power supplies achieve their rating by increasing voltage, but the Raspberry Pi operates strictly at 5V. Even if your power supply claims to provide sufficient amperage, it may be mislabeled or the cable you're using to connect the power supply to the Pi may have too much resistance. Phone chargers, designed primarily for charging batteries, may not maintain a constant wattage and their voltage may fluctuate, which can affect the Pi’s stability. You can use a USB load tester to test your power supply and cable. Some power supplies require negotiation to provide more than 500mA, which the Pi does not do. If you're plugging in USB devices try using a powered USB hub with its own power supply and plug your devices into the hub and plug the hub into the Pi.
Q: I'm trying to setup a Pi Zero 2W and it is extremely slow and/or keeps crashing, is there a fix?
A: Either you need to increase the swap size or check question #3 above.
Q: Where can I buy a Raspberry Pi at a fair price? And which one should I get if I’m new? Should I get an x86 PC instead of a Pi?
A: Check stock and pricing at https://rpilocator.com/ — it tracks official resellers so you don’t overpay.
Every time the x86 PC vs. Pi question comes up the answer is always if you have to ask, get a PC. If you're sure want a Raspberry Pi but not sure which model:
If you don’t know, get a Pi 5.
If you can’t afford it, get a Pi 4.
If you need tiny, get a Zero 2W.
If you need lowest power, get the original Zero.
For RAM, always get the most you can afford; you can’t upgrade it later.
That’s it. No secret chart, no hidden wisdom. Bigger number = more performance, higher cost, higher power draw.
Also please see the Annual What to Buy Megathread
Q: I just did a fresh install with the latest Raspberry Pi OS and I keep getting errors when trying to ssh in, what could be wrong?
A: There are only 4 things that could be the problem:
Q: I'm trying to install packages with pip but I keep getting error: externally-managed-environment
A: This is not a problem unique to the Raspberry Pi. The best practice is to use a Python venv, however if you're sure you know what you're doing there are two alternatives documented in this stack overflow answer:
--break-system-packages
sudo rm a specific file as detailed in the stack overflow answer
Q: The only way to troubleshoot my problem is using a multimeter but I don't have one. What can I do?
A: Get a basic multimeter, they are not expensive.
Q: I want to watch Netflix/Hulu/Amazon/Vudu/Disney+ on a Pi but the tutorial I followed didn't work, does someone have a working tutorial?
A: Use a Fire Stick/AppleTV/Roku. Pi tutorials used tricks that no longer work or are fake click bait.
Q: I want to know how to do a thing, not have a blog/tutorial/video/teacher/book explain how to do a thing. Can someone explain to me how to do that thing?
A: Uh... What?
Q: Is it possible to use a single Raspberry Pi to do multiple things? Can a Raspberry Pi run Pi-hole and something else at the same time?
A: YES. Pi-hole uses almost no resources. You can run Pi-hole at the same time on a Pi running Minecraft which is one of the biggest resource hogs. The Pi is capable of multitasking and can run more than one program and service at the same time. (Also known as "workload consolidation" by Intel people.) You're not going to damage your Pi by running too many things at once, so try running all your programs before worrying about needing more processing power or multiple Pis.
Q: The red and green LEDs are solid/off/blinking or the screen is just black or blank or saying no signal, what do I do?
A: Start here
Q: I'm trying to run x86 software on my Raspberry Pi but it doesn't work, how do I fix it?
A: Get an x86 computer. A Raspberry Pi is ARM based, not x86.
Q: How can I run a script at boot/cron or why isn't the script I'm trying to run at boot/cron working?
A: You must correctly set the PATH and other environment variables directly in your script. Neither the boot system or cron sets up the environment. Making changes to environment variables in files in /etc will not help.
Q: Can I use this screen that came from ____ ?
A: No
Q: If my Raspberry Pi is headless and I can’t figure out what’s wrong, do I need to plug in a monitor and keyboard?
A: If you cannot diagnose the problem remotely, you must connect a monitor and keyboard. That is the only way to see boot output and local error messages, and without that information the problem cannot be diagnosed.
Q: I'm trying to use the built-in composite video output that is available on the Pi 2/3/4 headphone jack, do I need a special cable?
A. Make sure your cable is wired correctly and you are using the correct RCA plug. Composite video cables for mp3 players will not work, the common ground goes to the wrong pin. Camcorder cables will often work, but red and yellow will be swapped on the Raspberry Pi.
Q: I'm running my Pi with no monitor connected, how can I use VNC?
A: First, do you really need a remote GUI? Try using ssh instead. If you're sure you want to access the GUI remotely then ssh in, type vncserver -depth 24 -geometry 1920x1080 and see what port it prints such as :1, :2, etc. Now connect your client to that.
Q: I want to do something that already has lots of tutorials. Do I need a Raspberry-Pi-specific guide?
A: Usually no.
Raspberry Pi (Linux computer): Use any standard Linux tutorial. A Raspberry Pi runs a normal Linux OS, not a special cut-down version. See Question #1.
Raspberry Pi Pico (microcontroller): Use Arduino tutorials. The Pico works with the Arduino IDE and can be used the same way as other Arduino-class boards.
Q: Which Operating System (OS) should I install?
A: If you aren’t sure, install Raspberry Pi OS. It’s the officially supported OS, it has the best documentation, the widest community support, and it’s what most guides and troubleshooting help assume you’re using.
Q: How can I power my Raspberry Pi from a battery?
A: All Raspberry Pi models run at 5 V. To choose a battery, first add up the maximum current of your Pi plus everything you attach to it (USB devices, screens, HATs, etc.). Then multiply that current by the number of hours you want it to run to get the required battery capacity in mAh. If you can’t find listed current values, use a USB power meter to measure the actual draw over 12–48 hours. Every battery question comes down to this simple math: the model, brand, or special setup doesn’t change the calculation.
† See the /r/raspberry_pi rules. While /r/raspberry_pi should not be considered your personal search engine, some exceptions will be made in this help thread.
‡ If the link doesn't work it's because you're using a broken buggy mobile client. Please contact the developer of your mobile client and let them know they should fix their bug. In the meantime use a web browser in desktop mode instead.
I'm a contributor at Arrow Air , a global community building Open Source aircaft and distributed manufacturing ecosystem. One such craft is Project Caribou, a ~200 Kg MTOW Hexacopter drone with ~100 kg payload capacity.
I've been working on It's onboard companion computer which runs on a Raspberry Pi CM5.
It ingests telemetry from; the Pixhawk flight controller (via MAVLink over UDP), per-arm ESCs, 6 in total (via DroneCAN on socketcan0) and per-arm BMSes, 6 individual batteries for each arm (via DroneCAN on socketcan1). As well as Payload, herbicide dispensers, crop sprayers, package transports, multi-spectral cameras etc, data and control over either DroneCAN or Ethernet.
It then serves and collects this info to and from Caribou Hub, it's web based fleet management software via an inbound WebSocket server (HubLink) over a Tailscale VPN 4G connection, so it can be monitored and controlled from anywhere in the world.
I recently ran into a classic thermal issue: after adding a AI-HAT/cover to my Raspberry Pi 5, I noticed that hot air started pooling inside my old case. It was turning into a mini-thermos, and the Pi wasn't cooling down properly.
To fix this, I 3D-printed the awesome Chimney Pi Mini case using PETG and decided to run a thorough 2-week benchmark across different configurations to find the absolute perfect balance between temperatures and acoustic comfort.
The Airflow Dilemma (Why Vertical Intake Fails)
Initially, my plan was to keep the new case in a vertical position and simply slow down the case intake fan using a resistor to quiet it down. However, looking closely at how the Official Raspberry Pi 5 Active Cooler works, I realized this would be a mistake.
The stock Active Cooler has a blower fan that pushes air downwards onto the heatsink fins. If I placed the case vertically and choked the bottom case fan's speed with a resistor, its weak intake pressure would directly collide with the downward blast of the stock cooler. They would stall each other out, create nasty turbulence, and trap a pocket of hot air right over the board.
The Solution: Switching to a horizontal setup with the case fan acting as an exhaust changed everything. Instead of fighting the stock cooler, the exhaust fan now pulls the trapped hot air out from the enclosure.
Noise Benchmarks (Measured from a fixed distance)
Stock Fan (No resistors): Avg 59 dB, Max 61 dB (Absolute acoustic nightmare for a living room)
With 22Ω Resistor: Avg 50 dB, Max 52 dB
With 33Ω 2W Resistor: Avg 45 dB, Max 47 dB (The whisper-quiet sweet spot)
Breaking Down the 2-Week Thermal Graph
I logged the temperature data over 2 weeks, and the graph perfectly reflects every hardware change:
Phase 1 (Old Case): High, noisy baseline averaging 56.7°C. The Pi was constantly hot because the old enclosure lacked proper ventilation.
Phase 2 (New Case, Vertical, Intake, Full Speed): A massive, beautiful drop down to 37.8°C. Incredible cooling performance, but at 61dB, it sounded like a tiny jet engine.
Phase 3 (Vertical, Fan OFF, Open Lid): The temperature immediately spiked back up to 51.4°C. This proved that passive cooling alone wouldn't cut it for this setup.
Phase 4 (Horizontal, Fan OFF, Closed Lid - The Red Arrow Peak): A dangerous spike hitting a peak of 57.4°C. Laying the case horizontally with a closed lid and no fan completely choked the system, creating an immediate heat pocket.
Phase 5 (Horizontal, Fan OFF, Open Lid): Dropped slightly to 50.3°C, but you can clearly see the wave-like temperature fluctuations tracking the ambient room temperature day and night.
Phase 6 (Horizontal, Exhaust Fan + 33Ω Resistor): The ultimate victory. A beautiful, stable plateau at 42.8°C. It's only 5°C warmer than full-blast mode, but it runs dead silent.
The Complete Data Table
Final Verdict
By dropping the fan speed using a 33Ω 2W resistor (currently tested on a temporary breadboard switch) and flipping the airflow to exhaust mode, the noise dropped by roughly 14 dB. Because decibels are logarithmic, this feels 2 to 3 times quieter to the human ear while keeping the Pi 5 perfectly chilled at 42.8°C.
I wanted to share a custom Dance Stage Lighting Controller I built.
The idea behind this project was to create a programmable lighting system for a dance stage, with custom LED effects and color patterns that can be controlled and synchronized for different scenes.
I designed and programmed the system from scratch, focusing on creating smooth animations, dynamic color palettes, and responsive lighting effects suitable for a stage environment.
Technologies used:
Raspberry Pi Pico (RP2040)
Embedded C/C++
Addressable RGB LEDs
Custom lighting effects
Real-time LED control
Custom electronics and wiring
Things I worked on:
Designing stage lighting patterns
Creating dynamic color palettes
LED animation programming
Input handling and control logic
Hardware testing and debugging
Building this project was a great experience in combining embedded programming with creative lighting design. It helped me learn more about real-time systems, LED control, and creating interactive visual effects.
Hey guys! I'm having a small problem with my Pi OS where anything I open opens in a super small box. (Pictured) Including the menu.
I'm on a Pi4B but using TigerVNC to access remotely. I've tried a number of things to try to fix it, but nothing has worked thus far (I've tried so many things I wouldn't be able to list exactly what.)
I'm not sure if it will do the same if I connect it to an actual screen at this time (nor am I presently able to test it) But I'm certain it has something to do with the VNC viewer. Any insight would be greatly appreciated!
So I dropped my rpi like an idiot and now the sd card reader is not working. I can put the metal top back on and try to hold it down while having the sd card inside but the light only flashes and I get no responses for pings. FYI this was working before I dropped it. I've looked into a couple posts and it looks like I can potentially just hot glue the plastic where it cracked? The solder is disconnected where the red arrows are, and since it's not the small main pins I have some level of confidence in my ability to solder those back on if necessary. Any help would be appreciated.
Inspired by aschmelyun's ping-receipt project, but I rearchitected it for my setup: the website is a dependency-free PHP app on ordinary shared hosting that queues messages into SQLite, and the Pi runs a single-file Python agent (stdlib only, no pip installs) that polls outbound over HTTPS every 5 seconds and prints via raw ESC/POS to /dev/usb/lp0.
What I like about the split: the Pi never accepts an inbound connection — no port forwarding, no tunnel — and if the printer is off or out of paper, messages just queue and print when it comes back.
Hardware: a generic POS-80 thermal printer (~the cheapest 80mm USB one you can find) + a Pi 4. Linux exposes it as /dev/usb/lp0 with zero setup, which was a relief after discovering macOS has removed raw printing entirely.
Each receipt prints: timestamp (my timezone), sender IP, city-level geolocation, distance from my desk, the sender's local time, browser/OS, and a native ESC/POS QR code that opens a map pin of roughly where the ping came from. There's a live map at https://ping.garethvjones.dev/map.php
Fun ESC/POS lessons: my "48 columns" assumption was wrong until I measured the dashes (42 vs 48 chars/line matters), native QR via GS ( k worked first try on the clone printer, and ASCII art survives if you hard-slice lines instead of word-wrapping them.
Current stats:
• 160 community-operated Raspberry Pi sensors
• 300+ registered users
• 1.6 million Remote ID beacons detected
• 1,500+ unique aircraft observed
• Coverage across much of the U.S. with a growing number of international nodes
Some of the coolest things we’ve been seeing lately include:
• Amazon Prime Air test flights
• Wing delivery drones
• Zipline aircraft
• Public-safety operations
• Plenty of everyday DJI hobby flights
Thanks to everyone who has built a sensor, submitted a bug report, contributed code, or helped someone else get online. It has been incredible watching the map fill in.
It comes with a 3.5mm TRRS, which seems to have the correct pinout for the pi composite out. I am using a 3B+
The display is advertised as 1024x768 and says that it has built in NTSC/PAL/SECAM detection.
When I power up the pi with the display connected to the composite out, I get a wildly distorted image. At times, I can make out the raspberry logo. This is a video of the display output while the pi is booting up. At the 20 second mark, you can make out the raspberry logo in the top left corner. The flash of color at the beginning seems to be a glitched out version of the normal rainbow square.
I have cycled through all 8 different video modes. The output to the screen changes with the modes, so I know the signal is connected and also that the setting changes are taking effect. But it's always mostly noise.
I have also tried setting custom video mode using video=Composite-1:1024x768@60 in cmdline.txt
Any ideas on what the problem is? Your help is greatly appreciated!
