Dumping A Zelda SNES ROM, And Learning A Few Things Along The Way

August 31, 2018 by 12 Comments

For many of us, being given a big old DIP ROM from nearly thirty years ago and being told to retrieve its contents would be a straightforward enough task. We’d simply do what we would have done in the 1980s, and hook up its address lines to a set of ports, pull its chip select line high, and harvest what came out of the data lines for each address.

But imagine for a minute that an old-fashioned parallel ROM is a component you aren’t familiar with, as [Brad Dettmer] did with the ROM from a SNES Zelda cartridge. We’ve seen plenty of reverse engineering stories with ancient computing gear as their subject, but perhaps it’s time to accept that some of the formerly ubiquitous devices are edging towards that sort of status.

So [Brad] takes us through the process of using the Saleae logic analyser to interrogate the chip while an Arduino stepped through its address lines, and the lesson is probably that while it seems like a sledgehammer to crack a nut it is important to factor in that unfamilarity. If you’d never worked with a 1980s ROM, it would make sense to use the tool you are familiar with, wouldn’t it?

Anyway, all’s well that ends well. While we’re on the subject of Nintendo ROMs, have a read about extracting the boot ROM from a cloned Game Boy.

This Hackable Phone Makes WiFi Calls.

August 24, 2018 by 24 Comments

Over the years, we’ve seen dozens of projects that sell themselves as an ‘Open Source’ cellphone, a hackable cellphone, or some other confabulation of a microcontroller, screen, and a cellular module. The WiPhone is not one of these projects. That’s not to say it’s not an Open Source phone that’s intended to be hackable. No, this is a DIY phone that doesn’t make cellular calls, because this is a phone that only works with SIP and VoIP apps. It’s a WiPhone, and something a lot of us have been waiting for.

The hardware for this WiFi enabled phone is extremely minimal, but there are some interesting tricks up its sleeve. Instead of letting the main microcontroller handle capturing all the button presses, the team behind the WiPhone are using a SN7326 key-scan controller. This cheap part is able to scan 64 buttons, although there are only 25 buttons on the phone. The audio board is a  WM8750BL, a cheap codec with a stereo microphone interface and a 400 mW speaker driver. The display is a simple SPI TFT, and apart from the microcontroller, that’s about it.

But it’s the microcontroller that makes it, and for that we turn to the incredible ESP-32. This chip has enough power to play Doom, be a Game Boy, and in this case, make and receive calls from a VoIP provider, scan and connect to WiFi networks, and yes, it can even play snake.

While this is just about the simplest phone you can imagine, and it only works where there’s a WiFi network, a device like this could be invaluable. And really, these days how far are you from a WiFi network you’re already connected to anyway?

MIDI Association Releases Spec For TRS Jacks

August 23, 2018 by 27 Comments

The MIDI spec was released in 1983, and for more than thirty years every synthesizer, drum machine, and piece of computer hardware with MIDI has sported an enormous DIN-5 jack on the back. Why did they choose such a large connector? Well, MiniDIN connectors hadn’t even been invented yet, and today even MiniDIN connectors are rarely-seen, obsolete connectors.

In the last decade, MIDI has found its way into some very small machines. Those Pocket Operators have MIDI sync, you can control a Game Boy with MIDI using the right hardware, and the cute little Korg synths also have MIDI tucked away in there somewhere. You can’t put a DIN-5 jack on those things, leading to some weird implementations of MIDI over non-standard connectors.

Now the MIDI Association has weighed in on the situation. There’s now a spec for MIDI over 2.5mm and 3.5mm TRS jacks. In just a few short decades, you’ll be able to connect MIDI gear with an audio aux cable.

Although there are five connectors in a DIN-5 jack, most implementations use only two connectors to send and receive data. Synth manufacturers have capitalized on this fact and cheap TRS connectors to build their own implementation of MIDI using smaller connectors, sometimes with incompatable pinouts.

Now, though, there’s a standard. For TRS connectors, the tip is pin 5 on the DIN-5, the ring is pin 4, and the sleeve is pin 2. It sends and receives data to synths and drum machines from 1983, and it doesn’t use gigantic connectors.

The only caveats to the new MIDI standard is that 2.5mm TRS connectors are recommended, and that protection circuitry is strongly recommended in the case a headphone driver is inevitably connected to a MIDI device. Other than that, everything’s coming up roses, and this opens up the door to MIDI jacks that are much, much easier to source.

Twitch Plays Battling Robots?

August 8, 2018 by 3 Comments

Audience interaction reached an all-time high in 2014 with Twitch Plays Pokemon, an online gaming stream where viewers were able to collaboratively command an emulated Game Boy playing Pokemon Red. Since then, the concept has taken off. Today, we see this extended to robots in the real world, with [theotherlonestar]’s Twitch Chat Controlled Robots.

The build is one that takes advantage of modern off-the-shelf components – an ESP8266 provides the brains, while a Pololu Zumo provides a ready to go robot chassis to save time on the mechanical aspects of the build. An L298N dual motor controller then handles motive power.

The real ingenuity though, is teaching the robots to respond to commands from Twitch chat. The chat is available in a readily parsable IRC format, which makes programming around it easy. [theotherlonestar] created a command set that enables the robots to be driven remotely by stream viewers, and then outfitted the ‘bots with hammers with which to fight, as well as a fedora to tip, if one is so inclined.

It’s a cool build, and one which shows further promise as Twitch continues to reduce stream & chat latency. We look forward to seeing future battles, but the first one already excites.

Interested in where it all began? Check out our Twitch Plays Pokemon coverage from way back when. Video after the break.

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It’s 1984, And You Can’t Afford A Computer. Never Mind, Have This Pop-Up Paper One Instead!

July 16, 2018 by 40 Comments

It’s an oft-derided sentiment from a Certain Type of Older Person, that the Youth of Today don’t know how lucky they are with their technology. Back when they were young they were happy with paper and string! Part of the hilarity comes from their often getting the technology itself wrong, for example chastising the youngsters for their iPods and Game Boys when in reality those long-ago-retired devices are edging into the realm of retrotechnology.

But maybe they have a point after all, because paper and string could be pretty good fun to play with. Take the example presented  in a Twitter thread by [Marcin Wichary]. A pop-up book from 1984 that presents the inner workings of a computer in an astounding level of detail, perhaps it stretches the pop-up card designer’s art to the limit, but along the way it makes a fascinating read for any retrocomputing enthusiast. Aside from the pop-up model of the computer with an insertable floppy disk that brings text onto the screen we see at  first, there is a pop-up keyboard with a working key, a peer inside the workings of a floppy disc, a circuit board complete with a paper chip that the reader can insert into a socket, and a simulation of a CRT electron bean using a piece of string. A Twitter thread on a book is not our normal fare, but this one is something special!

Did any of you have this book when you were younger? Perhaps you still have it? We’d love to hear from you in the comments. It’s probably not the type of book we normally review, but we’ve been known to venture slightly outside tech on that front.

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Hackaday Links: June 24, 2018

June 24, 2018 by 31 Comments

What do you do if you’re laying out a PCB, and you need to jump over a trace, but don’t want to use a via? The usual trick is using a zero Ohm resistor to make a bridge over a PCB trace. Zero Ohm resistors — otherwise known as ‘wire’ — are a handy tool for PCB designers who have backed themselves into a corner and don’t mind putting another reel on the pick and place machine. Here’s a new product from Keystone that is basically wire on a tape and reel. It’s designed to jump traces on a PCB where SMD zero ohm resistors and through-hole jumpers aren’t possible. I suppose you could also use it as a test point. They’re designed for high current applications, but before we get to that, let’s consider how much power is dissipated into a zero ohm resistor.

By the way, as of this writing, Mouser is showing 1,595 for Keystone’s 5100TR PCB jumpers in stock. They come on a reel of 1,000, and a full reel will cost you $280. This is significantly more expensive than any SMD zero ohm resistor, and it means someone bought four hundred of them. The electronic components industry is weird and you will never understand it.

There’s a new product from ODROID, and you want it. The ODROID-GO is a Game Boy and Sega Master System emulator running on an ESP-32, has a fantastic injection molded case, and looks phenomenal.  You can buy it now for $32. Does this sound familiar? Yes, a few months ago, the PocketSprite was released. The PocketSprite is the tiniest Game Boy ever, and a project [Sprite_TM] introduced to the world at the 2016 Hackaday Superconference.

This week, the speaker schedules for two awesome cons were announced. The first is HOPE, at the Hotel Penn on July 20th. Highlights of this year? [Mitch Altman] is talking about DSP, [Chelsea Manning] will be on stage, someone is talking about HAARP (have fun with the conspiracy theorists), and someone is presenting an argument that [Snowden] is an ideological turd. The speaker schedule for DEF CON was also announced. The main takeaway: god bless the CFP board for reigning in all the blockchain talks, the Nintendo Switch was broken wide open this year, but there’s only a talk on the 3DS, and there’s more than enough talks on election hacking, even though that was a success of propaganda instead of balaclava-wearing hackers.

The C.H.I.P. is no more, or at least that’s the rumor we’re running with until we get some official confirmation. When it was introduced, the C.H.I.P. was a Linux system on a chip with complete register documentation. It appears the end of C.H.I.P. is upon us, but have no fear: there’s a community building the PocketC.H.I.P., or the C.H.I.PBeagle. It’s a single board computer based around the OSD3358 from Octavo, the same system found in the PocketBeagle. Source in KiCAD, and people are working on it. Thanks [smerrett79] for the tip.

DIY Talkbox Gives You More Bounce To The Ounce

June 14, 2018 by 10 Comments

Back in the 70s, you couldn’t swing a macrame plant hanger around a record store without knocking over numerous displays of albums featuring talkboxes. They were all over 70s music, kind of like how almost every 80s song has a sax solo and/or Michael McDonald on backing vocals. Not sure you’ve heard one being used? Trust us, you definitely have and just don’t realize it.

Talkboxes are essentially an amplifier and a speaker contained in a box. The speaker is the acoustic diaphragm type used in bullhorns and civil defense sirens. You run your guitar, keyboard, or electrified hurdy gurdy into the box, and instead of driving a horn, the sound travels up a clear plastic tube and into your mouth. Your mouth, fine resonant cavity that it is, becomes the final effect pedal. Any way you can manipulate it will shape the sound coming from the instrument. Flap those lips, and suddenly you’re talking like a robot. Who wouldn’t want one of these?

So they aren’t complicated, but you wouldn’t know it from the price of commercial ones. [mosivers] really digs the sound and wanted to build one, so he scoured the internet to figure out how to do so properly and shared his findings in this Instructable. The most important bit is the compression driver. The drivers that featured in the original talkboxes aren’t made anymore, but there are suitable replacements for ~$40.

The next most important part is a high-pass filter to keep really low frequencies from damaging the driver. After that it’s down to the amplifier, some passives, and the all-important tube. You could laser cut an enclosure as [mosivers] did, or be the first person in history to reuse a Danish butter cookie tin for something other than sewing supplies. Boogie on down past the break and let’s groove tonight.

Speaking of the 80s, here’s a DIY talkbox built on a Game Boy.

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