emulator

172 Articles

Classic Calculators Emulated In Browser

January 30, 2023 by 24 Comments

The Multiple Arcade Machine Emulator, now known simply as MAME, started off as a project to emulate various arcade games. The project is still adding new games to its library, but the framework around MAME makes it capable of emulating pretty much any older computer. The computer doesn’t even need to be a gaming-specific machine as the latest batch of retro hardware they’ve added support for is a number of calculators from the 90s and early 00s including a few classics from Texas Instruments.

Since no one is likely to build an arcade cabinet version of a TI-89, all of these retro calculators are instead emulated entirely within a browser. This includes working buttons and functions on an overlay of each of these calculators but also pixel-accurate screen outputs for each of these. The graphing calculators have more of what we would consider a standard computer screen, but even the unique LCDs of some of the more esoteric calculators are accurately replicated as well thanks to the MAME artwork system.

There are a number of calculators implemented under this project with a full list found at this page, and the MAME team has plans to implement more in the future. If you’re looking for something fun to do on a more modern calculator, though, take a look at this build which implements ray tracing on a TI-84 Plus CE.

Thanks to [J. Peterson] for the tip!

A pink and white Leapster GS handheld console sits on a wooden table. It has a white D-pad and two large pink action buttons. A power cord extends from the bottom and a headphone cable comes out the top.

RetroArch On A LeapFrog Leapster GS

January 30, 2023 by 12 Comments

Retro games are a blast, and even more so when you can bring the fun on the go. [mac2612] has developed a custom retroarch-based firmware for the Leapster GS and LeapPad2. (via Bringus Studios on YouTube)

We covered Linux on the Leapster before, but Retroleap seems better documented (and still up on the internet). Installation is done over the command line with sshflash, also by [mac2612], after booting the Leapster or LeapPad2 into “Surgeon Mode.” Since the stock bootloader remains intact, you can always return the LeapFrog to its default state if anything gets wiggy by reflashing the device via the LeapFrog Connect App.

The default system includes emulators for NES, SNES, GBA, Genesis, Atari 800, and MAME. Performance varies, but some PS1 games have even run successfully on the device.

If you’d like to see some other LeapFrog hacks, checkout this LeapFrog TV Running DOOM or Composite Video Out on the DIDJ.

Continue reading “RetroArch On A LeapFrog Leapster GS” →

From A 6502 Breadboard Computer To Lode Runner And Beyond

January 17, 2023 by 2 Comments

As disruptive and generally unpleasant as the pandemic lockdowns of 2020 were, they often ended up being a catalyst for significant personal growth. That was often literal growth, thanks to stress eating, but others, such as [Eric Badger], used the time to add skills to his repertoire and build a breadboard 6502 computer and so much more.

For those of you looking for a single endpoint to this story, we’re sorry to disappoint — this isn’t really one of those stories. Rather, it’s a tale of starting as a hardware newbie with a [Ben Eater] 6502 breadboard computer kit, and taking it much, much beyond. Once the breadboard computer kit was assembled, [Eric] was hooked, and found himself relentlessly expanding it. At some point, he decided to get the classic game Lode Runner going on his computer; this led to a couple of iterations of video cards, including a foray away from the breadboards and into PCB design. That led to a 6502 emulator build, and a side quest of a Raspberry Pi Pico Lode Runner appliance. This naturally led [Eric] to dip a toe into the world of 3D printing, because why not?

Honestly, we lost track of the number of new skills [Eric] managed to add to his toolkit in this video, and we’re sure this isn’t even a final accounting — there’s got to be something he missed. It’s great stuff, though, and quite inspirational — there’s no telling where you’ll end up when you start messing around with hardware hacking.

Continue reading “From A 6502 Breadboard Computer To Lode Runner And Beyond” →

Replace Your Automatic Transmission With A Bunch Of Relays

January 5, 2023 by 80 Comments

A “Check Engine” light on your dashboard could mean anything from a loose gas cap to a wallet-destroying repair in the offing. For [Dean Segovis], his CEL was indicating a fairly serious condition: a missing transmission. So naturally, he built this electronic transmission emulator to solve the problem.

Some explanation may be necessary here. [Dean]’s missing transmission was the result of neither theft nor accident. Rather, he replaced the failed automatic transmission on his 2003 Volkswagen EuroVan with a manual transmission. Trouble is, that left the car’s computer convinced that the many solenoids and sensors on the original transmission weren’t working, leaving him with a perfectly serviceable vehicle but an inspection-failing light on the dash.

To convince the transmission control module that a working automatic was still installed and clear the fourteen-odd diagnostic codes, [Dean] put together a block of eight common automotive relays. The relay coils approximate the resistance of the original transmission’s actuators, which convinces the TCU that everything is hunky dory. There were also a couple of speed sensors in the transmission, which he spoofed with some resistors, as well as the multi-function switch, which detects the shift lever position. All told, the emulator convinces the TCU that there’s an automatic transmission installed, which is enough for it to give the all-clear and turn off the Check Engine light on the dash.

We love hacks like this, and hats off to [Dean] for sharing it with the VW community. Apparently the issue with the EuroVan automatic transmissions is common enough that a cottage industry has developed to replace them with manuals. It’s not the only questionable aspect of VW engineering, of course, but this could help quite a few people out of a sticky situation.

Continue reading “Replace Your Automatic Transmission With A Bunch Of Relays” →

Encoding NTSC With Your Hands Tied

December 25, 2022 by 10 Comments

Generally, when trying to implement some protocol, you are constrained by your hardware and time. But for someone like [EMMIR], that’s not enough. For example, NTSC-CRT is a video signal encoding/decoding simulator with no hardware acceleration, floating point math, or third-party libraries. Just basic C.

While NTSC has officially gone dark in America, people still make their own ATTiny-powered transmitters. NTSC is a bit of a strange standard and is sometimes referred to as never-twice-the-same color, but it does produce a distinct look.

That look is what [EMMIR] was going for. It encodes a message in a ppm format into NTSC and then back in ppm with some configurable noise. It can do this in real-time as an effect in [EMMIR’s] engine or on a rendered image via a CLI. It looks incredible, and there’s something very satisfying. There’s a video after the break showing off the effect. The code is pretty short and easy to read.

Continue reading “Encoding NTSC With Your Hands Tied” →

Blinky Project Is 6502s All The Way Down

December 24, 2022 by 19 Comments

Virtually any platform you might find yourself programming on has some simple method of running a delay. [Joey Shepard] got rather creative on a recent project, though, relying on a rather silly nesting method that we’re calling 6502s All The Way Down.

The project in question was a simple PCB that was shaped like a robot, with blinking LED eyes. Typically, you’d simply reach for the usual sleep() or delay() function to control the blink rate, but [Joey] went off-piste for this one. Instead, the PIC32 on the board runs a 6502 emulator written in MIPS assembly. This emulated 6502 is then charged with running a further 6502 emulator coded in 6502 assembly, and so on, until there’s 6502 emulators running six-deep on the humble microcontroller. The innermost emulator runs a simple program that blinks the LED eyes in a simple loop. With the overhead of running six emulators, though, the eyes only blink at a rate of roughly once every two seconds.

It’s an amusing and complicated way to write a blink program, and we applaud [Joey] for going to all that trouble. We imagine it was a great way to learn about programming the PIC32 as well as emulation in general. Meanwhile, if you’re working on your own emulator feats, be sure to let us know!

Ultimate Game And Watch Has Support For NES

December 9, 2022 by 2 Comments

We’ve talked about feature creep plenty of times around here, and it’s generally regarded as something to be avoided when designing a prototype. It might sound good to have a lot of features in a build, but this often results in more complexity and more difficulty when actually bringing a project to fruition. [Brendan] has had the opposite experience with this custom handheld originally designed for Game and Watch games, though, and he eventually added NES and Game Boy functionality as well.

As this build was originally intended just for Game and Watch games, the screen is about the size of these old games, and while it can easily mimic the monochrome LCD-style video that would have been present on these 80s handhelds, it also has support for color which means that it’s the perfect candidate for emulating other consoles as well. It’s based around a Raspberry Pi Zero 2W and the enclosure is custom printed and painted. Some workarounds for audio had to be figured out, though, since native analog output isn’t supported, but it still has almost every feature for all of these systems.

While we’ve seen plenty of custom portable builds from everything from retro consoles to more modern ones, the Game and Watch catalog is often overlooked. There are a few out there, but in this case we appreciate the feature creep that allowed this build to support Game Boy and NES games as well.