Sony’s Playstation 5 console and its DualSense controllers aren’t exactly new, but the triggers of the controllers have a genuinely interesting design that is worth examining. The analog triggers on the PS5 controllers are generally described as having “variable resistance”, but it turns out that’s not the whole story. Not only is the trigger capable of variable resistance when being pressed, but it can also push back in variable ways and with varying amounts of force. How it works is pretty clever.
The feedback for the trigger assembly is handled by a lever, a geared wheel, and a worm gear on an electric motor. Under normal circumstances, nothing interferes with the trigger at all and it works like a normal analog trigger. But when the motor moves the lever into place, trigger movement now has to overcome the added interference with a mechanical disadvantage. The amount of resistance felt can be increased a surprising amount by having the motor actively apply additional force to counter the trigger’s movement.
That’s not all, either. The motor can also actively move the lever into (or out of) position, which means that pulling the trigger not only has the ability to feel smooth, mushy, or stiff in different places, but it can also actively push back. This feedback can be introduced (or removed) at any arbitrary point along the trigger’s range of motion. A trigger pull can therefore feel like it has a sharp breakpoint, a rough travel, a hard stop, an active recoil, or any combination of those at any time.
It’s a little hard to describe, but you can get a better idea of it all works in practice by watching part of this teardown by [TronicsFix] (video cued to about 9:17 where the trigger teardown begins.) It’s also embedded below, so give it a peek.
The first thing we notice about this portable PS2 is that the plastic looks like a consumer-grade shell, not a 3D printed case. It comes from [GingerOfOz], who has lots of portable conversions under his belt, so we are not surprised this looks like a genuine Sony device. When you are as experienced as he, details like plastic texture, and button selection, are solved problems, but shouldn’t be taken for granted by us mortals.
Of course, this isn’t just pretty, and if it weren’t functional, we wouldn’t be talking about it. The system plays nearly all PS2 titles from USB memory. The notable exceptions are the ones that refuse to load without a Dualshock controller. Rude. If you’re wondering if it plays games at full speed, yes. It achieves authentic speed because it uses a PS2 slim motherboard which gets cut down by a Dremel. Custom PCBs provide the rest of the hardware, like volume buttons and battery charging. There is no optical drive since they are power hogs, so your cinematic cut scenes may lag, and load times are a little longer.
The first Playstation is quickly approaching three decades since its release, and while this might make some of us who were around for that event feel a little aged, the hardware inside these machines isn’t getting any younger either. Plenty of people are replacing the optical drive in the original hardware with an optical drive emulator as they begin to fail, and with that comes the option for several other modifications to the hardware like this in-game reset mod.
In-game reset is a function that allows a console to be reset via a controller button combination rather than pressing the console’s reset button directly. Especially for devices modified with either the XStation or PSIO drive emulators, this can be a handy feature to have as this method can more easily take the user back to the emulator menu as well as physically reset the device. The modification is a small PCB which attaches to the controller port and, unlike previous versions, only requires a single pin to be soldered to the Playstation’s control board.
If you’re someone who enjoys playing games on original hardware rather than a patchwork of emulators, this could be an excellent addition to your PS1 that still allows most of the original feel and experience the PS1 offered. The drive emulator can greatly expand the range of the hardware as well, much like this NES cartridge which similarly expands the capabilities of that much older system.
The exploit is considerably more complex this time around, but [Bradlin] does an excellent job of breaking it down for those who want the gritty details. The short version is that missing boundary checks in the PlayStation’s built-in memory card handling routines mean a carefully formatted “block” on the memory card can get the console to execute a small 128 byte payload. That’s not a lot of room to work with, but it ends up being just enough to load up additional code stored elsewhere on the memory card and really kick things off.
Unlike tonyhax, which was designed specifically to allow the user to swap their retail Tony Hawk disc with a game burned to a CD-R, [Bradlin]’s FreePSXBoot is presented as more of a generic loader. As of right now, it doesn’t allow you to actually play burned games, although its inevitable that somebody will connect those last few dots soon.
If you want to check out the progress so far, all you need is wire a PlayStation memory card up to an Arduino, write the provided image to it, and stick it in the slot. [Bradlin] says the exploit doesn’t work 100% of the time (something else that will surely be addressed in future releases), but it shouldn’t take too many attempts before you’re greeted with the flashing screen that proves Sony’s 27 year old console has now truly been bested.
Aptly named tonyhax, this exploit uses a classic buffer overflow found in the “Create Skater” mode in Tony Hawk 2, 3, and 4. When the game sees a custom character saved on the memory card it will automatically load the name field to show it on the screen, but it turns out the developers didn’t think to check the length of the name before loading it. Thanks to this oversight, a long and carefully crafted name can be used to load an executable payload into the console’s memory.
That payload could be anything, such as a homebrew game, but in this case [Marcos] went all in and developed a simple tool that unlocks the console’s optical drive so it will play games burned to CD-Rs. Once the tonyhax exploit has been loaded, you simply swap the authentic Tony Hawk disc for whatever burned title you want to play. So far every game tested has worked, even those that span across multiple discs.
[Marcos] is providing not only the save files ready to load on your PlayStation memory card (either through a PC tool, or with the help of a hacked PS2), as well as the complete source code for tonyhax. This opens the door to the exploit being used to load other tools, emulators, and indie games, but as the PlayStation homebrew scene is relatively limited when compared to newer consoles, the demand might be limited.
Compared to the traditional physical modifications used to play copied games on the PlayStation, this new software approach is far more accessible. Expect to see memory cards with this exploit preinstalled hit your favorite import site in the very near future.
No matter how it happens, losing one or more fingers is going to change one’s life in thousands of ways. We’re a manipulative species, very much accustomed to interacting with the world through the amazing appendages at the ends of our arms. Finding ways around the problems that result from amputations is serious business, of course, even when it’s just modifying a game console controller for use with a prosthetic hand.
We’ve gotten to know [Ian Davis] quite well around these parts, at least from his videos and Instagram posts. [Ian]’s hard to miss — he’s in the “Missing Parts Club” as he puts it, consisting of those who’ve lost all or part of a limb, which he has addressed through his completely mechanical partial-hand prosthetic. As amazing as the mechanical linkages of that prosthetic are, he hasn’t regained full function, at least not to the degree required to fully use a modern game console controller, so he put a couple of servos and a Trinket to work to help.
An array of three buttons lies within easy reach of [Ian]’s OEM thumb. Button presses there are translated into servo movements that depress the original bumper buttons, which are especially unfriendly to his after-market anatomy. Everything rides in an SLA-printed case that’s glued atop the Playstation controller. [Ian] went through several design iterations and even played with the idea of supporting rapid fire at one point before settling on the final design shown in the video below.
It may not make him competitive again, but the system does let him get back in the game. And he’s quite open about his goal of getting his designs seen by people in a position to make them widely available to other amputees. Here’s hoping this helps.
The original Sony PlayStation came out just in time for CD piracy to really start taking off. Aware of this threat to sales, Sony engineers included a copy protection and region locking mechanism that placated executives and annoyed end-users alike. [MattKC] explores how this copy protection worked, and how you can burn your own modchip at home for just a few dollars.
Sony’s method of copy protection relied on steps taken during the manufacturing process, pressing a special groove into the game media that regular CD burners couldn’t replicate, a topic our own [Drew Littrell] has covered in depth. This groove contained a four letter code that could be read by the console, corresponding to the region in which the game was sold. The console would read this groove on startup, and check that the code in the game matched the code in the console before booting. Modchips circumvent this by injecting a spoof code into the console that matches the local region, regardless of what is read off the disc. This has the effect of both allowing users to run bootleg CD-Rs, homebrew code, as well as games from other regions.
Today, we’re blessed with the Internet and cheap hardware. As [MattKC] demonstrates, it’s no longer necessary to mail-order a chip from a dodgy ad in the back of a games magazine; instead, one can download source code and flash it to a commodity PIC microcontroller for just a few bucks. With the chip soldered in to the relevant points of the PS1’s motherboard, you’re good to go.