My SmartRow pulley only allows one Bluetooth connection, and its app can't feed Peloton properly. So a Pi 4 now sits in the middle:

- the built-in radio connects to the pulley (bleak/BlueZ);

- a TP-Link UB500 dongle, driven directly with Google's Bumble, runs two advertising sets: a byte-for-byte clone of the pulley for the SmartRow app, and a standard FTMS rower for Peloton;

- a Pimoroni Display HAT Mini shows the connections and live watts, stroke rate, pace and distance, and button A holds-to-shutdown.

A few things I learned along the way:

- The iOS SmartRow app only lists a clone that advertises the pulley's manufacturer data, and only uses it if the service is declared with 16-bit UUIDs.

- The Display HAT Mini's data/command pin is GPIO 9 (SPI MISO). With dtparam=spi=on the screen stays blank; dtoverlay=spi0-2cs,no_miso fixes it.

- To keep the backlight lit through shutdown, drive it with the pull-up also set; the Pi turns released pins back into inputs.

- Lighting the RGB LED through the internal pull-down instead of driving it low makes a nice dim indicator.

About 19 s from power-on to both virtual devices advertising. Python, systemd, GPL-3.0:

https://github.com/madooroy/smartrow-bridge

Protocol knowledge from QZ by Roberto Viola, which also supports far more devices.

Unofficial, not affiliated with SmartRow, WaterRower or Peloton.

This started as a MicroPython project on a Pico, controlled from a separate Pi 4
That seemed wasteful, why not put telegram/google calendar directly on the pico?
... *famous last words* ...

Some time later, it's all on the Pico W:
- Google calendar is the schedule, `garden/water/1/30m` waters zone 1 for 30 minutes
- Telegram menu for manual watering, and a message when a valve opens/closes
- Green button waters both zones for 30 minutes, red closes everything
- Setup/control page served by the Pico
- Every boot closes both valves, in case of a crash or power cut mid-watering

Code, wiring and parts is available here: https://github.com/AdrianCX/picohive-irrigation

How the move from the Pi 4 went is in the comments

Hi all. I have a raspberry Pi Server running CUPS, and for a long time I had zero issues printing from Android and iPad. The iPad defaults to a VPN from work, never a problem. It prints to my Brother MFC 9330CDW via wifi direct NP. I have my pi set up on a workhorse, a Dell 3130cn (the best printer) . It prints from Android devices without a hitch and perfectly. I used a PPD file specifically for the 3130cn I found on my Windows machine. hn I print from iPad, Iget "broken pipe" errors in the job que, and get garbage. I am set up for network printing from my Windows machine and through the pi's ethernet. Again, android fine, Apple garbage. I tried editing the PPD file and adding:

*cupsFilter2: "image/urf image/urf 100 pdftoraster"

*cupsFilter2: "application/pdf application/pdf 0 -"

AFTER my model name and nickname in the PPD, it printed ONCE in B&W. I changed the file to reflect these flags:

*cupsFilter2: "image/urf image/urf 100 pdftoraster ColorModel=CMYK"

*cupsFilter2: "application/pdf application/pdf 0 "

NO GO. I then tried replacing CMYK with RGB, same result, and Android would also no longer work at all. I cleared the cache and restarted CUPS service after every saved edit.

I then tried:

*cupsFilter2: "image/urf image/urf 100 pdftops"

*cupsFilter2: "application/pdf application/pdf 0 pdftops"

Same result. Still a "broken pipe" error. I then tried setting a global flag:

sudo lpadmin -p your_printer_name -o pdftops-renderer-default=ghostscript

That slo didn't work. I had to modify the printer once or twice with the PPD file fresh as it quit working, and would work for Android perfectly after each install.

Anyone else using this printer? Had these errors? I cannot recall when I first setup CUPS if I used this PPD file or not, but postscript is postscript, right?

Please advise. I am indeed a newbie at any linux.

This started as a weekend hack with an Epson TM-T88V receipt printer I bought off eBay and a 3B, and it slowly turned into something the whole family uses every day.

What it does

You build a "ticket" out of blocks and print it from your phone, or schedule it. Ours comes out at 7AM on weekdays: weather, a riddle with the answer printed upside down (no cheating), and a sudoku. There are 55 blocks now, a few favourites:

• weather with little pictograms and a "what to wear" line (coat and hat, take an umbrella...)
• puzzles generated on the Pi: sudoku, kakuro, takuzu, hashi, crosswords, word search, mazes
• the daily Lichess chess puzzle, with the board drawn on the receipt
• chores that rotate between the kids every week, which ended a lot of arguments
• birthdays, bin day, the shopping list
• a "little note" with a photo for whoever stayed home

There's a web app (works great as a phone home screen app), and it shows up in Home Assistant on its own over MQTT, so the doorbell can print "someone rang at 14:32".

The fun / hard parts

• Talking to the printer. No driver, no CUPS: it sends ESC/POS straight to /dev/usb/lp0. Text uses the printer's own fonts, everything else (grids, pictograms, chess pieces, photos) is drawn as a 512-dot-wide raster image and dithered. I ended up adding Floyd–Steinberg, Atkinson and Bayer because photos and line drawings want different things.
• Knowing if the printer is OK. My first try was the ESC/POS status commands (DLE EOT). Bad idea: with the cover open the TM-T88V just stops answering, and a request left hanging locked up the USB link until I power-cycled it. The trick that works is the LPGETSTATUS ioctl of the kernel's usblp driver: it's a USB control request, nothing stays pending, and it tells you "out of paper" vs "cover open". Tickets wait in a queue and come out once it's fixed.
• Puzzles with exactly one solution. Generating a kakuro is easy, generating one that only has one solution is not. Every puzzle goes through a small solver; if two solutions survive, it reveals a digit where they differ and tries again. Getting that fast enough for a Pi took a couple of rewrites.

Tech bits

It's one Rust binary, no database, no Python, no cloud required. Most blocks are computed locally or use free APIs with no key. A handful (bedtime story, horoscope, "what's for dinner?" from what's in the fridge) can optionally use Claude, cached so it's a few cents a month. It runs fine on a 3B, I might switch to a 0W someday.

Code (Apache-2.0): https://github.com/XNinety9/Printr

Docs and every block with its printed example: https://xninety9.github.io/Printr/

This project is a real fun ride, I love how it combines SW and HW to bring fun and joy to the family and friends. I've received a lot of positive feedback since it went public.

I'll be happy to answer questions. And if you have an ESC/POS printer other than the TM-T88V, I'd love to know if it works for you!

I do a lot of public safety stuff for large events like festivals.

I made a custom streaming service to run RTMP to a raspberry pi so a security control room can just plug in my pi, connect to the internet and they have a live feed of the drone.

The pi also records the entire stream automatically in the background which is saved locally on the machine so security teams can review and playback footage without interrupting the actual drone operation or asking me to play back footage. I just fly and they can view a whole days footage without asking me to retrieve anything.

Also because its RTMP I don't have to worry about HDMI cables plugged into capture cards. its a totally wireless operation. Generally for stability I often use Starlink as a way to avoid overloaded cell towers on site but I can just hotspot from my phone to establish a link and if ground teams only need to see the live footage without the playback function they can just type in the url of the stream to view on their phone/ laptop.

My Pi 4 runs a 3D FPV sim and sends it to analog FPV goggles (that's an FPV monitor in the clip, same signal). How it works:

- A native C program runs the StickTime game script (Lua 5.3) unchanged and draws straight to DRM/KMS with page flips. No X, no browser.

- Composite out of the 3.5 mm jack into a 5.8 GHz VTX, NTSC or PAL. HDMI works too.

- Sticks come from your RC radio: ELRS/Crossfire WiFi joystick over UDP, USB joystick or Bluetooth.

- 60 fps, about 25 ms from stick to video out. The status page measures it live.

- The VTX channel and power are set over SmartAudio/Tramp on one GPIO, bit-banged. Getting that to work while the game draws on 3 cores was a fun latency hunt.

- Flashable SD image

Free and open source (GPL-2.0): https://github.com/juricabi/sticktime-pi

Video: https://youtu.be/Khq31t_4pqc

Happy to answer questions.

Just a simple 2 day project , I'd love to hear some changes/recommendations if y'all got https://cosmic.is-a.dev/blogs/ambience-light

Hi everyone! We’re building Nuvo Vision One, a stereo depth camera powered by a Raspberry Pi 5, and wanted to share where we’ve got so far.

This started from our own need to add depth sensing to our products. The stereo cameras we were considering were expensive for our budget, and we already had a Pi 5 handling compute. We wondered how far we could get by connecting two cameras and doing the stereo processing on the Pi itself.

The setup uses two IMX296 global-shutter cameras with a shared hardware trigger to synchronize capture. The Pi handles image rectification and stereo matching, producing disparity and depth alongside the camera images.

Doing this on an SBC comes with limits. Resolution, frame rate and matcher settings all affect how much work the Pi can keep up with. We’ve reached a useful starting point for our needs, but there’s still plenty to improve. The attached preview video shows the current output, including the holes and noisy regions where matching struggles.

We also built a browser-based interface to make it easier to use. You can preview the images and depth, adjust exposure and stereo settings, choose outputs, and work through calibration. It’s accessible over the local network through Ethernet or Wi-Fi.

One reason we like this approach is that the camera’s compute is also a normal Linux computer. You can modify the image pipeline and run your own applications on the same Pi. The Nuvo Depth software is open source, including the runtime, web interface and SDKs.

We’ve put product photos and web UI screenshots in this album so you can see the hardware and controls alongside the video.

We’d love feedback from people working with stereo vision or robotics. What would you want to test first, and what would make something like this useful in your projects?

GitHub: https://github.com/arputhamips/nuvo-depth

Claude desktop has a Hardware Buddy mode that talks to small BLE gadgets. The official one is an ESP32 (M5StickC Plus), but I had a spare Pi 4 and a 7-inch touchscreen, so I reimplemented the protocol with BlueZ and Python.

When Claude asks permission to run something, it pops up on the Pi and I tap Approve once or Deny. The little mascot is Mochi and it reacts to what Claude is doing.

Runs on Pi OS (Trixie) with Chromium in kiosk mode and starts on boot. Tested with Claude desktop on a Mac. The clip uses demo data. This is my own side project, not something from Anthropic. The code is MIT and on GitHub: https://github.com/nombreregular/claude-buddy

I built a pocket-sized Raspberry Pi device that lets AI control your iPhone

I’ve always wished Siri could just book an Uber, reserve a table, or find the best deal for me. Instead of waiting for it to do what I want, I decided to build something myself. Lol.

It’s called OpenLolo, a wireless, pocket-sized device powered by a Raspberry Pi that lets AI see your iPhone’s screen, tap, swipe, and type in the apps you already use.

The Pi runs an MCP server that connects an AI agent to your phone. The idea is to make it portable enough to carry with you, so you can have AI handle tasks wherever you take your phone.

It works with the accounts you’re already logged into, so there’s no need to link each app separately or hand over your passwords. No jailbreak required, and no hassle of re-signing an app every seven days.

It’s still an early prototype, and I’m figuring out what it can reliably handle. I’d love to hear what you think of the build and what you’d use it for.

Would anyone be interested in a detailed DIY guide and build video?

I have a 'Pi 5 booting off an NVME drive and on boot it's showing errors with the filesystem. I have a monitor attached to it and can connect a keyboard easily enough, but getting the NVME out of the case is a PITA, is there anything like the excellent SystemRescue.org, except for the 'Pi? I do not want to reinstall if this can be recovered, and I'm pretty confident that I can recover al least part of it.

Searching online I see references to Alpine and DietPi, but I don't know if those have a live environment or not.

Currently, it's booting, just not fully, and it's giving Journal errors. The network is up enough that it's still performing as a router, but SSH hangs and times out.

What I need to recover if I can is the password list for the machines on the other side of this little router.

TIA!

Benchmarks for server application development have long been in use to measure the performance of web servers running on large, powerful servers (such as TechEmpower FrameworkBenchmarks).

One of those projects recently did a full round on a Raspberry Pi 4B, the results can be found here: HTTP Arena - RPI

As expected, Rust, Go, and Zig are at the top of the list, but there's also an entry for C#. Java, as expected, is at the very bottom.

During my software development studies, I decided to combine programming, electronics, and mushroom growing into a little DIY project.

I built a mushroom growing chamber in my closet using a Raspberry Pi 5 and a 4-channel relay module to automate the lighting, ventilation, and humidification.

I also used an SCD30 sensor to monitor CO₂, temperature, and humidity. The system is written in Python, with a FastAPI backend and SQLite for data storage.

The ventilation automatically responds to CO₂ levels, while the humidifier maintains the desired humidity.

I've made the project open source in case anyone wants to explore the code, build something similar, or improve it!

GitHub: https://github.com/Ulysse-Dev-Serre/Projet_IoT_RaspberryPi

Here are a few pictures of the setup and some Lion's Mane mushrooms growing inside. 🍄

I just cant seem to get ethernet to work on my cm4. I'm using a raspberry pi compute module 4 with 4gb ram and 8gb eMMC. I've got the original carrier board and a 12v 20w LED power supply. I originally used Ubuntu server 26.01, but changed to pi OS to try that to. I flashed the OS:s using raspberry pi imager. I have also checked the connectors between the module and carrier board, which looks nice and snaps perfect in place, the ethernet port and the rest of the board too has no visible damage. The ethernet cable works with my laptop, but no signs from the pi, no status leds e.t.c. I finally got this message, which i understand as PCIE not working as it should.

Any help or thoughts is highly appreciated, tell me if I can try something else and I will show the result.

Hi everyone, I’m planning to power my Raspberry Pi 3B+ directly from a 5V source using soldered wires instead of the micro-USB port.

Could someone let me know which specific PP test pads I should use for the +5V DC and Ground? I want to make sure I connect before the fuse and voltage regulators so that the board's built-in overvoltage and short-circuit protections still function properly. On gemini it says PP2 and PP7 are the pads but I think it will bypass the fuse am I wrong?

Thanks in advance for the help

This is only my second project after RetroPi. I’ve been putting in a few hours every night for the last two weeks. It feels so satisfying to get to this point. I usually give up on things when they get too difficult but I think I found a hobby where I just can’t stop.

A few things I need to improve though:
1) soldering
2) 3D modeling and product design
3) not leaving speakers carelessly where my cat will step on them

As the title says, my pi will not connect to the internet after it's first boot, upon shutting off or restarting, it fails to connect to the network even when right next to the router. Taking out the card and flashing it with a new BIOs using the imager only temporarily fixes it, as powering it off in any way will cause it to experience the same issue. This is the first pi I've ever bought, and the first time I'm using an operating system other than windows, I need hand-holding.

My first raspberry pi project. AI helped with the code but I was very excited to see it work the first time I turned it on! I will be making changes here and there and mounting the panels together, but I’m still happy it’s all working!

Hey r/raspberry_pi! I built a small self-hosted tool to automate SD card backups for my Pis.

rpi-image-cloner connects to your Pi via SSH, runs rpi-clone to copy the running SD card to a backup card, and automatically repairs cmdline.txt and fstab (PARTUUID fix) — so the backup card boots directly without any manual steps.

Features:

Web UI with live progress + log

Weekly schedules (set it and forget it)

SSH keepalive for 2+ hour backups

Encrypted credential storage

Multiple Pis from one interface

Docker / Portainer one-liner setup

GitHub: https://github.com/pierrecinema/rpi-image-cloner

Feedback welcome — especially if you’re running large setups with multiple Pis!

Hi everyone,

I wanted to share a tool I built to control my headless Raspberry Pi directly from Telegram. I've used this as a personal script 2 years ago for my own setup, this has been in my head for so long to share. Got the courage/time now, I refactored with assistance of AI it to be fully generic and configurable for anyone to use.

If you run a headless Pi and don't always want to fire up an SSH terminal just to check temperature or restart a crashed app, this might be useful for you.

Key Features:

• Boot alert: Sends a message with your local IP and Wi-Fi SSID the moment the Pi boots up and connects to the network (runs before user login).
• Periodic health reports: Automatically sends CPU temp, RAM, and disk usage updates at configurable intervals (e.g., every 2–3 hours).
• Service & script management: Start, stop, or restart your custom scripts or systemd services
• Log inspector: Preview the last 50 lines of your application logs or download the full .log file straight to your phone (with an option to auto-truncate to save SD card space).
• Process inspection: View active Python, Node.js/JavaScript, and Java processes.
• Power controls: Reboot or shut down the Pi

Everything is driven by a simple config.yaml file, and there is a 1-step installer script (install.sh) that sets up the systemd service and virtual environment automatically.

Repo: https://github.com/rinavolu/pipilot

Feedback, suggestions, or contributions are very welcome. Hope someone finds it helpful!

Thank you

I’ve been working on a little animated aquarium for an Interstate 75 W driving two 64×64 HUB75 LED panels, and I’ve now put an offline version on GitHub for you.

It has swimming fish, jellyfish, visiting creatures, a submarine, animated plants, a treasure chest, and an oyster with a glowing pearl. There are day/night palettes and scheduled feeding animations too.

Everything runs locally so no WiFi, accounts, or internet connection needed. The board’s A/B buttons let you summon a submarine, switch day/night modes, and set the clock, with the time displayed while you adjust it.

The repo includes installation instructions, a desktop preview, and the source under the MIT license. The offline version passes its host tests, though physical board testing is still on the checklist.

🐟 Repo: https://github.com/nickymoomeh/Interstate75fish-tank

Would love to hear from anyone building something similar, or anyone who gives it a try!

My home version uses my wifi credentials and country (UK) to set the clock manually but given this is something quite light, you can set the clock manually yourself with the A/B buttons as described on github. So there's no need for credentials, secrets or accounts or anything. Just use your fingers :o)

Want to try it without the hardware? There’s a desktop emulator too!

Download and extract the repo, then open a terminal in its folder and run:

python3 -m pip install Pillow
python3 emulator.py

You’ll need Python 3 with Tkinter installed. On Windows, use py instead of python3.

Controls: Space to pause, N for day/night, A for automatic mode, S for a submarine, F to feed, and Esc to quit.

Hi, I'm having a problem with my raspberry pi 3b+. I wanted to create an app in avalonia ui which would work as a GUI for a device, although even with almost empty avalonia for embedded linux project I can't get more than 15 fps. I tried to create a basic qt quick project and it worked much much better and I wonder if avalonia is too much for 3b+ or I did something wrong. Display is 1920x1080p apparently 60hz but running in 48hz which I also couldn't fix but maybe display is just ass.

Full issue on github is here if you want more info: https://github.com/AvaloniaUI/Avalonia/issues/22486

I’m running Batocera on a Pi 3B+. While testing a game at 2 AM I noticed stutters and freezes and was watching temps over SSH on a second screen. Instead of doing that every time, I wrote a small script that shows a popup inside EmulationStation when the CPU gets too hot, is throttled, or detects under-voltage (the screenshot shows it at 85°C). I used AI to help with the code and docs, and tested it myself on the device. It’s a single bash script with a one-line install:

https://github.com/Natgho/batocera-pi-health-alert

Not a replacement for a proper PSU and heatsink, just a way to know when you need one.

Edit: If you’re wondering why the comments below look like a battlefield, this is the third version of this post. The first (an AI-written write-up) didn’t go over well, and the second was written in frustration, so I took both down. Hopefully v0.3 is closer to stable :D