Building a bluetooth DAC with Raspberry Pi Zero W

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Sami Pietikainen has written an article detailing the build of his Bluetooth DAC using Raspberry Pi Zero W:

My car comes with a built-in Bluetooth hands-free but unfortunately it does not support audio streaming. Luckily there is an AUX input available which uses a regular 3,5 mm jack. Perfect opportunity for a DIY project. I built the Bluetooth DAC using Raspberry Pi Zero W and a DAC hat. This post depicts the details of this project.

See the full post on Page Fault Blog.

PocketPi MK2

img_20190518_140600 A smaller thinner PocketPi from Facelesstech:

Thinner with a simpler design but packing the same feature as before. At its heart is a raspberry pi zero W with a 3.5″ screen 480×320. It has all the GPIO pins available what aren’t being used by the screen. Its powered by a 2500mAh battery and has one full sized usb port. Its controlled by a bluetooth keyboard with trackpad

More details on Facelesstech blog.

Check out the video after the break.

RetroZero (retropie handheld)

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Facelesstech published a new build:

I’ve been on a quest for while now trying to build a retropie handheld that was functional but didn’t break the bank. So far I’ve made ZeroBoy – A poor man’s retropie “portable” and a follow-up ZeroBoy rev C – An improved poor mans retropie portable. These were great but I think I have made a much better system with all the features included.

More details  on Facelesstech blog.

Check out the video after the break.

Tiny particle sensor node with decorative case

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Lucky Resistor published a new build:

This article is about a small sensor node with a decorative case. It is based on the Raspberry Pi Zero W board with a custom sensor shield on top.
I publish all hardware files for a simple version of the sensor, so you should be able to build this kind of sensor nodes and use it to monitor anything you like. You can also extend/modify the design easily with additional sensors. Nevertheless, the case lid design is based around the Plantower PMSA003 particle sensor. It has all required air vents for this use.

More details on Lucky Resistor homepage.

Pi Keeps Cool at 1.5 GHz

Hackers have a long history of overclocking CPUs ranging from desktop computers to Arduinos. [Jacken] wanted a little more oomph for his Pi Zero-Raspberry Pi-based media center, so he naturally wanted to boost the clock frequency. Like most overclocking though, the biggest limit is how much heat you can dump off the chip.

[Jacken] removed the normal heat sink and built a new one out of inexpensive copper shim, thermal compound, and super glue. The result isn’t very pretty, but it does let him run the Zero Pi at 1.5 GHz reliably. The heat sink is very low profile and doesn’t interfere with plugging other things into the board. Naturally, your results may vary on clock frequency and stability.

[Jacken] staggers the shim pieces to afford more exposed surface area. Although copper is a good conductor of heat, using multiple pieces probably mitigates some of the advantage. On the other hand, using thermal compound between the pieces should reduce the microgaps between shims, so that will help.

In addition to overclocking, [Jacken] made some power measurements with all cores active and came up with a surprisingly low current draw (well under 1A). That’s a sample of one, though, so you should probably make your own measurements if it matters

This isn’t the first [Jacken] overclock we’ve seen but the new aspect is the low profile heat sink. If you are just in it for sport, you can overclock an Arduino, even. You can run at 65 MHz, as long as you don’t mind supply liquid nitrogen.


Filed under: Raspberry Pi

Smart Projector With Built-in Raspberry Pi Zero

You’ve heard of smartphones but have you heard of smart projectors? They’ve actually been around for a few years and are sort of like a TV set top box and projector combined, leaving no need for a TV. Features can include things like streaming Netflix, browsing in Chrome, and Skyping. However, they can cost from a few hundred to over a thousand dollars.

[Novaspirit]  instead made his own cheap smart projector. He first got a $70 portable projector (800×480 native resolution, decent for that price) and opened it up. He soldered an old USB hub that he already had to a Raspberry Pi Zero so that he could plug in a WiFi dongle and a dongle for a Bluetooth keyboard. That all went into the projector.

Examining the projector’s circuit board he found locations to which he could wire the Raspberry Pi Zero for power even when the projector was off. He lastly made the Raspberry Pi dual-bootable into either OSMC or RetroPie. OSMC is a Linux install that boots directly into a media player and RetroPie is a similar install that turns your Raspberry Pi into a gaming machine. You can see a timelapse of the making of it and a demonstration in the video after the break.

This isn’t the only cool thing [Novaspirit] has done with one of these $5 Raspberry Pi Zeros. We also saw him turn one into a USB stick for plugging into a laptop, using the USB connection as an Ethernet connection.


Filed under: Raspberry Pi

Thwomp Drops Brick on Retro Gaming

[Geeksmithing] wanted to respond to a challenge to build a USB hub using cement. Being a fan of Mario Brothers, a fitting homage is to build a retro-gaming console from cement to look just like your favorite Mario-crushing foe. With a Raspberry Pi Zero and a USB hub embedded in it, [Geeksmithing] brought the Mario universe character that’s a large cement block — the Thwomp — to life.

[Geeksmithing] went through five iterations before he arrived at one that worked properly. Initially, he tried using a 3D printed mold; the cement stuck to the plastic ruining the cement on the face. He then switched to using a mold in liquid rubber (after printing out a positive model of the Thwomp to use when creating the mold). But the foam board frame for the mold didn’t hold, so [Geeksmithing] added some wood to stabilize things. Unfortunately, the rubber stuck to both the foam board and the 3D model making it extremely difficult to get the model out.

Like [Han] in carbonite, that's a Rapsberry Pi Zero being encased in cement
Like [Han] in carbonite, that’s a Raspberry Pi Zero being encased in cement
Next up was regular silicone mold material. He didn’t have enough silicone rubber to cover the model, so he added some wood as filler to raise the level of the liquid. He also flipped the model over so that he’d at least get the face detail. He found some other silicone and used it to fill in the rest of the mold. Despite the different silicone, this mold worked. The duct tape he used to waterproof the Raspberry Pi, however, didn’t. He tried again, this time he used hot glue – a lot of hot glue! – to waterproof the Pi. This cast was better, and he was able to fire up the Pi, but after a couple of games his controller stopped working. He cracked open the cement to look at the Pi and realized that a small hole in the hot glue caused a leak that shorted out the USB port on the Pi. One last time, he thought, this time he used liquid electrical tape to waterproof the Pi.

The final casting worked and after painting, [Geeksmithing] had a finished cement Thwomp console that would play retro games. He missed the deadline for the USB Hub Challenge, but it’s still a great looking console, and his video has a lot of detail about what went wrong (and right) during his builds. There’s a great playlist on YouTube of the other entries in the challenge, check them out along with [Geeksmithing]’s video below!


Filed under: nintendo hacks, Raspberry Pi

Hackaday Links: November 6, 2016

Here’s a life protip for you: get really, really good at one video game. Not all of them; you only want to be good – top 10% at least – at one video game. For me, that’s Galaga. It’s a great arcade game, and now it’s IoT. [justin] has been working on publishing high scores from a Galaga board to the Internet. The electronics are actually pretty simple – just a latch on a memory address, and an ESP8266 for comms.

On with the mergers and acquisitions! Lattice has been sold to Canyon Bridge, a Chinese private equity firm, for $1.3 Billion. Readers of Hackaday should know Lattice as the creators of the iCE40 FPGA platform, famously the target of the only Open Source FPGA toolchain.

The Internet of Chocolate Chip Cookies. Yes, it’s a Kickstarter for a cookie machine, because buying a tube of pre-made cookie dough is too hard. There is one quote I would like to point out in this Kickstarter: “Carbon Fiber Convection Heating Element (1300W) is more energy-efficient than traditional electric elements and heats up instantly.” Can someone please explain how a heating element can be more efficient? What does that mean? Aren’t all resistive heating elements 100% efficient by default? Or are they 0% efficient? The Internet of Cookies broke my brain.

The USB Rubber Ducky is a thumb-drive sized device that, when plugged into a computer, presents itself as a USB HID keyboard, opens up a CLI, inputs a few commands, and could potentially do evil stuff. The USB Rubber Ducky costs $45, a Raspberry Pi Zero and a USB connector costs $6. [tim] built his own USB Rubber Ducky, and the results are great.


Filed under: Hackaday Columns, Hackaday links

Pi Zero Powered Skateboard

There’s something to be said for whizzing around town on your own automatic personal transport. It’s even better when you’ve built it yourself. That’s just what [The Raspberry Pi Guy] did – built a Wiimote controlled, Raspberry Pi Zero powered skateboard and whizzed around Cambridge to show it off.

It’s a fairly simple build – skateboard, battery, motor and mount, controller, Wiimote and Pi Zero. The Raspberry Pi controls the motor controller which in turn controls the motor speed. The Python code that [The Raspberry Pi Guy] wrote comes in at around a hundred lines and manages the motor controller and the Bluetooth connection to the Wiimote, which is used to control the board’s speed while the user controls the steering. [The Raspberry Pi Guy] says he’s gotten up to 30 km/h on the skateboard, which, given a powerful enough motor and a non-bumpy surface isn’t hard to believe.

It may seem a bit of overkill, running a bit of Python on a Raspberry Pi to run a motor (others have done it with something simpler) but it’s a fun project nonetheless. [The Raspberry Pi Guy] describes where he got the parts to put the skateboard together and has released the Python code on his GitHub page.


Filed under: Raspberry Pi

Give Your RPi a Cool FPGA Hat

Need additional, custom IO for your Raspberry Pi? Adding an FPGA is a logical way to expand your IO, and allow for high speed digital interfaces. [Eric Brombaugh]’s Icehat adds a Lattice iCE5LP4K-SG48 FPGA in a package that fits neatly on top of the Raspberry Pi Zero. It also provides a few LEDs and Digilent compatible PMOD connectors for adding peripherals. The FPGA costs about six bucks, so this is one cheap FPGA board.

The FPGA has one time programmable memory, but can also be programmed over SPI. This allows the host Pi to flash the FGPA with the latest bitstream at boot. Sadly, this particular device is not supported by the open source Icestorm toolchain. Instead, you’ll need Lattice’s iCEcube2 design software. Fortunately, this chip is supported by the free license.

Icehat is an open source hardware design, but also includes a software application for flashing a bitstream to the FPGA from the Pi and an example application to get you started. All the relevant sources can be found on Github, and the PCB is available on OSHPark.

While this isn’t the first pairing of a Raspberry Pi and FPGA we’ve seen, it is quite possibly the smallest, and can be built by hand at a low cost.


Filed under: Raspberry Pi