Google Maps, Now On The NES

Many years ago, Google created one of its famous April Fools jokes suggesting it would make an 8-bit version of Google Maps for the original Nintendo Entertainment System. [ciciplusplus] decided it needed to become a reality, however, and set to work. (Video, embedded below.)

It’s a suitably blocky, low-resolution implementation, but it nevertheless is a mapping app running on an NES. Zooming in and out is via the A and B buttons, while the D-pad is used to scroll. Country and city labels are rendered on the map in the relevant areas in a charming old-school font.

The project uses a Raspberry Pi 3A+ and a Cypress Semiconductor FX2LP microcontroller, which fits inside a NES cartridge. It works the same way as the earlier NES Doom project which uses the Raspberry Pi to feed data to the NES’s Picture Processing Unit. It’s achieved with a simple bit of code burned on a ROM inside the cartridge, which boots up the NES and primes it to receive data from the Raspberry Pi via the FX2LP.

In current form, it’s not capable of doing much more than allowing the user to scroll around and zoom in on parts of the map. We’d love to see a fully-fledged version that could deliver driving directions or similar, however. If you end up achieving such a feat, be sure to let us know. Continue reading “Google Maps, Now On The NES”

Neat Little Airboat Built From Old Drone Parts

Multirotor drones tend to need quality and well-matched parts in order to stay balanced and in the air. However, crash enough drones and you might find you’ve got plenty of mistmatched bits and pieces lying around. In just this vein, [Jason Suter] decided to raid his junk box and built himself a little FPV airboat using spare parts.

The airboat consists of a 3D printed hull, paired with a separate power module. The power module houses the flight controller, and mounts twin motors on the rear. Fitted with three-blade props, they propel the boat and allow it to be steered with differential thrust instead of a rudder. It’s then fitted with a camera to allow it to be piloted with an FPV headset.

Handling still isn’t perfect, and water on the FPV antenna causes some issues with video transmission. However, it’s a fun project that makes good use of old parts. Of course, if you’re having vibration problems with your own FPV projects, consider building a vibration-absorbing mount. Video after the break.
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Upgrade Board Adds GPIO Pins To Your Replica PDP-11

Like many Hackaday readers, [Steven Stallion] has had his eyes on the replica PDP-11 created by [Oscar Vermeulen] for some time now, and this summer he finally got the opportunity to build one himself. But while most owners might be content to just watch the Raspberry Pi based faux-retro computer blink away on a shelf, he wanted to explore putting the machine to more practical use. The end result is the PiDP-11 I/O Expander,  an add-on that lets the modern minicomputer interact with the world around it.

Developed after some discussion with [Oscar] himself, the Microchip MCP23016 based expander board fits neatly onto the PiDP-11 PCB, and [Steven] has made sure his installation guide meshes well with the replica’s documentation. The Pi’s I2C bus is actually broken out on the original PCB, so you just need to solder a header on and run some jumpers to where the expander is mounted. You’ll need to pull 5 V as well, and the installation guide has a few tips on convenient connection points.

The installed PiDP-11 I/O Expander

Each expander board gives you 16 GPIO pins which can be accessed over I2C, including support for interrupts which has been connected to GPIO 19 on the Raspberry Pi. [Steven] notes that you should be able to stack multiples of his expander up should you need even more free pins, though some fiddling with pull-up resistors and I2C addresses will likely be necessary.

The PCBs for the expander have been released under the two clause BSD license, so you’re free to spin up your own copies however you see fit. But if you’d like to save some time, [Steven] is offering assembled boards on Tindie.

Since [Oscar] first teased it at the 2015 Hackaday Supercon, we’ve been enamored with his fantastic PDP-11 replica. We’re always glad to see when somebody has picked up one of these wonderful kits, and doubly so when they’ve figured out a way to expand it in unexpected ways.

Detect Lightning Strikes With An Arduino

Lightning is a powerful and seemingly mysterious force of nature, capable of releasing huge amounts of energy over relatively short times and striking almost at random. Lightning obeys the laws of physics just like anything else, though, and with a little bit of technology some of its mysteries can be unraveled. For one, it only takes a small radio receiver to detect lightning strikes, and [mircemk] shows us exactly how to do that.

When lightning flashes, it also lights up an incredibly wide spectrum of radio spectrum as well. This build uses an AM radio built into a small integrated circuit to detect some of those radio waves. An Arduino Nano receives the signal from the TA7642 IC and lights up a series of LEDs as it detects strikes in closer and closer proximity to the detector. A white LED flashes when a strike is detected, and some analog circuitry supports an analog galvanometer which moves during lightning strikes as well.

While this project isn’t the first lightning detector we’ve ever seen, it does have significantly more sensitivity than most other homemade offerings. Something like this would be a helpful tool to have for lifeguards at a pool or for a work crew that is often outside, but we also think it’s pretty cool just to have around for its own sake, and three of them networked together would make triangulation of strikes possible too.

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Small sensor built into audio jack, held in tweezers

Measuring LED Flicker, With Phototransistor And Audio App

No one likes a flickering light source, but lighting is often dependent on the quality of a building’s main AC power. Light intensity has a close relation to the supply voltage, but bulb type plays a role as well. Incandescent and fluorescent bulbs do not instantly cease emitting the instant power is removed, allowing their output to “coast” somewhat to mask power supply inconsistencies, but LED bulbs can be a different story. LED light output has very little inertia to it, and the quality of both the main AC supply and the bulb’s AC rectifier and filtering will play a big role in the stability of an LED bulb’s output.

Mobile phone spectrum analyzer pointed at light source
The DIY photosensor takes the place of the microphone input.

[Tweepy] wanted to measure and quantify this effect, and found a way to do so with an NPN phototransistor, a resistor, and a 3.5 mm audio plug. The phototransistor and resistor take the place of a microphone plugged into the audio jack of an Android mobile phone, which is running an audio oscilloscope and spectrum analyzer app. The app is meant to work with an audio signal, but it works just as well with [Tweepy]’s DIY photosensor.

Results are simple to interpret; the smoother and fewer the peaks, the better. [Tweepy] did some testing with different lighting solutions and found that the best performer was, perhaps unsurprisingly, a lighting panel intended for photography. The worst performer was an ultra-cheap LED bulb. Not bad for a simple DIY sensor and an existing mobile phone app intended for audio.

Want a closer look at what goes into different LED bulbs and how they tick? We have you covered. Not all LED bulbs are the same, either. Some are stripped to the bone and others are stuffed with unexpected goodness.

ARM’s Chinese Venture Goes Sour

We’re used by now to many of the more capable microcontrollers and systems-on-chip that we use having an ARM core at their heart. From its relatively humble beginings in a 1980s British home computer, the RISC processor architecture from Cambridge has transformed itself into the go-to power-sipping yet powerful core for manufacturers far and wide. This has been the result of astute business decisions over decades, with ARM’s transformation into a fabless vendor of cores as IP at its heart. Recent news suggests that perhaps the astuteness has been in short supply of late though, as it’s reported that ARM’s Chinese subsidiary has gone rogue and detatched from the mothership taking the IP with it.

It seems that the CEO of the Chinese company managed to retain legal power when sacked by the parent company over questionable ties with another of his ventures, and has thus been able to declare it independent of its now-former parent. It still has the ARM IP up to the moment of detatchment and claims to be developing its own new products, but it seems likely that it won’t receive any new ARM IP.

What will be the effect of this at our level? Perhaps we have already seen it, as more Chinese chips such as the cheaper STM32 clones are likely to get low-end ARM cores as a result. It seems likely that newer ARM IP will remain for now in more expensive non-Chinese chip families, but in the middle of a semiconductor shortage it’s likely that we wouldn’t notice anyway. Where it will have a lasting effect is in future Chinese joint ventures by non-Chinese chip companies. Seeing ARM’s then-owner Softbank getting their fingers burned in such a way is likely to provide a disincentive to other companies considering a similar course. Whether ARM will manage to resolve the impasse remains to be seen, but it can hardly be a help to the rocky progress of their Nvidia merger.

See The Unseen With This Magnetic Field Visualizer

The average Hackaday reader likely knows, at least in the academic sense, what a magnetic field looks like. But as the gelatinous orbs in our skull can perceive only a tiny fraction of the EM spectrum, we have to take those textbook diagrams at face value. That is, unless you’ve got one of these nifty magnetic field visualizers developed by [Dr.Stone].

Using an XMC1100 microcontroller development board and a TLV49 3D magnetic sensor, the device is able to track the poles of a magnet in real-time and produce an approximation of what the field lines would look like on its electronic paper display. Relative field strength is indicated by the size of the visualization, which allows the user to easily compare multiple magnets. Incidentally, [Dr.Stone] notes that the current version of the hardware and software can only handle one magnet at a time; visualizing complex magnetic fields and more than two poles would take an array of sensors and likely a more powerful processor.

Do you need to visualize the field lines around a magnet? Perhaps not. But being able to quickly get an idea of how strong a magnet is and identify where its poles are could certainly come in handy. We’d like to see [Dr.Stone] take the project to the next phase and turn this into a handheld device for convenient workbench use. It would be a lot less messy than some of the previous methods we’ve seen for visualizing magnetic fields, though if you’re only worried about field strength, there’s arguably more straightforward ways to display it.

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