SD cards add cheap persistent memory to your project, but the holder takes a lot of board space. A smaller option is the microSD flash format. MicroSD cards are compatible with regular SD cards, and most come with a free adapter. We looked at four holders for our mini web server. Which should you choose? Read about our experience below. Continue reading “Parts: MicroSD Memory Card Holders”
If you want to make circuits for a living, what better way to impress a future employer than to hand them a piece of your work to take home? But even if you’re just hacking for fun, you can still turn your calling into your calling card.
We are inviting you to submit your coolest business card hacks for us all to admire, and the top three entries will win a $150 DigiKey shopping spree. If your work can fit on a business card, create a project page for it over on Hackaday.io and enter it in the 2024 Business Card Contest. Share your tiny hacks!
To enter, create a project for your hacked business card over at Hackaday IO, and then enter it into the 2024 Business Card Challenge by selecting the pulldown on the left. It’s that easy.
Continue reading “The 2024 Business Card Challenge Starts Now”
[Grug Huhler] built a simple Tayloe mixer and detector on a breadboard. He decided to extend it a bit to be a full-blown software defined radio (SDR). He then used WSJT-X to monitor FT8 signals and found that he could pick up signals from all over the world with the little breadboard system.
A Raspberry Pi Pico generates a quadrature clock that acts as the local oscillator for the radio. All the processing of the input signal to a quadrature signal is done with a 74LV4052A, which is nothing more than an analog multiplexer. In principle, the device takes a binary number from zero to three and uses it to connect a common signal to one of four channels. There are two common lines and two sets of four channels. In this case, only half of the chip is in use.
An antenna network (two resistors and a capacitor) couples the antenna to one of the common pins, and the Pi generates two square waves, 90 degrees out of phase with each other. This produces select signals in binary of 00, 01, 11, and 10. An op amp and a handful of passive components couple the resulting signals to a PC soundcard, where the software processes the data. The Pi can create clocks up to about 15 or 20 MHz easily using the PIO.
The antenna is a 20-meter-long wire outside, and that accounts for some of the radio’s success. There are several programs than can work with soundcard input like this and [Grug] shows Quisk as a general-purpose receiver. If you missed the first video explaining the Tayloe mixer design, you can catch it below the first video.
This isn’t the first breadboard SDR we’ve seen, but they all use different parts. We’ve even seen a one-bit SDR with three components total (not including the microcontroller). Seriously.
If you have software-defined radio hardware and you are only using someone elses’ software, you are missing out on half of the fun. [Tech Minds] shows you how easy it can be to roll your own software using GNU Radio Companion in a recent video.
GNU Radio usually uses Python, but with the companion software you rarely need to know any actual Python. Instead, you simply drag blocks around to represent filters, DSP processing, and other functions you need to create the processing for your application.
Humans are walking high voltage generators, due to all the friction with our surroundings, wide variety of synthetic clothes, and the overall ever-present static charges. Our electronics are sensitive to electrostatic discharge (ESD), and often they’re sensitive in a way most infuriating – causing spurious errors and lockups. Is there a wacky error in your design that will repeat in the next batch, or did you just accidentally zap a GPIO? You wouldn’t know until you meticulously check the design, or maybe it’s possible for you to grab another board.
Thankfully, in modern-day Western climates and with modern tech, you are not likely to encounter ESD-caused problems, but they were way more prominent back in the day. For instance, older hackers will have stories of how FETs were more sensitive, and touching the gate pin mindlessly could kill the FET you’re working with. Now, we’ve fixed this problem, in large part because we have added ESD-protective diodes inside the active components most affected.
These diodes don’t just help against ESD – they’re a general safety measure for protecting IC and transistor pins, and they also might help avoid damaging IC pins if you mix. They also might lead to funny and unexpected results, like parts of your circuit powering when you don’t expect them to! However, there’s an awesome thing that not that many hackers know — they let you debug and repair your circuits in a way you might not have imagined.
Continue reading “Hacker Tactic: Internal ESD Diode Probing”
When the Raspberry Pi 5 launched, many were left chomping at the bit after seeing the PCIe FPC connector alongside the promise that an ‘NVMe SSD HAT would be forthcoming’. Although the official Raspberry Pi NVMe HAT is still a long while off, the Polish company Pineberry Pi is ramping up to release its Top & Bottom versions of its very wittily called HatDrive.
They sent a prototype to [Jeff Geerling], who has been putting his grubby mitts all over them before putting together a video showing off the HatDrive Top, which can accept 2230 and 2242 size NVMe drives.
The primary goal of adding an NVMe drive to the RPi is of course to get rid of those slow and fragile SD cards. Although the SD card standard supports near-NVMe-like speeds with UHS-III, the Raspberry Pi 5 bottoms out at UHS-I, around 100 MB/s. Despite this, using an NVMe drive for booting still takes some work, as [Jeff] lays out in a clear article. Most of this involves tweaking the /boot/config.txt file to enable external PCIe support, editing the onboard EEPROM to change the boot order (in lieu of having a PC-like BIOS screen) and getting the OS image flashed onto the NVMe drive you intend to boot from.
Although things seem to work fine during [Jeff]’s testing, some caveats remain, such as the RPi 5 officially supporting only PCIe Gen 2 x1, with Gen 3 possible, but with potential data integrity issues. There’s also the fundamental limit of having only a single lane of PCIe available. If that’s no problem, then Pineberry Pi offers the aforementioned HatDrive Top for traditional HAT-style mounting, and a Bottom version that can accept up to 2280 format NVMe SSDs. Including the provided ribbon cables, you can order the Top and Bottom for €20 and €25.99 respectively, with the first batch to ship in early December.
Continue reading “Pineberry Pi HatDrive: Using NVMe SSDs With The Raspberry Pi 5”
The Raspberry Pi has come a long way since its humble origins, adding faster processors and better interfaces with each new generation. Now, the Raspberry Pi 5 has a lovely new PCIe port right on board, and [Jeff Geerling] has gone right ahead and slammed in an NVMe SSD as a boot drive.
[Jeff] explains that to use an NVMe to boot, you first have to modify /boot/config.txt to enable PCIe and modify the Raspberry Pi’s boot order. Once the bootloader is appropriately configured, you can boot straight off an SSD with Raspberry Pi OS installed. To get the operating system on to an NVMe drive, he recommends cloning an existing boot volume from a microSD install.
One of the primary reasons you might want to do this is speed. NVMe drives are generally a significant cut above even the best microSD cards, both in speed and reliability. [Jeff] also notes that you can use an NVMe SSD through a PCIe switch on the Pi 5 if you so desire, but you can’t currently boot with this configuration.
It’s a great feature to have on the Pi 5, and it follows on from the earlier implementation on the Raspberry Pi Compute Module 4. Video after the break.
Continue reading “Booting The Raspberry Pi 5 With An NVMe SSD”
