65F02 Is An FPGA 6502 With A Need For Speed

September 10, 2025 by Tyler August 8 Comments

Does the in 65F02 “F” stand for “fast” or “FPGA”? [Jurgen] doesn’t know, but his drop-in replacement board for the 6502 and 65c02 is out there and open source, whatever you want it to stand for.

The “f” could easily be both, since at 100 MHz, the 65f02 is blazing fast by 6502 standards–literally 100 times the speed of the first chips from MOS. That speed comes from the use of a Spartan 6 FPGA core to implement the 6502 logic; making the “f” stand for “FPGA” makes sense, given that the CMOS version of the chip was dubbed the 65c02. The 65f02 is a tiny PCB containing the FPGA and all associated hardware that shares the footprint of a DIP-40 package, making it a drop-in replacement. A really fast drop-in replacement.

You might be thinking that that’s insane, and that (for example) the memory on an Apple ][ could never run at 100 MHz and so you won’t get the gains. This is both true, and accounted for: the 65F02 has an internal RAM “cache” that it mirrors to external memory at a rate the bus can handle. When memory addresses known to interact with peripherals change, the 65f02 slows down to match for “real time” operations.

The USB adapter board for programming is a great touch.

Because of this the memory map of the external machine matters; [Jurgen] has tested the Commodore PET and Apple ][, along with a plethora of German chess computers, but, alas, this chip is not currently compatible with the Commodore 64, Atari 400/800 or BBC Micro (or at least not tested). The project is open source, however, so you might be able to help [Jurgen] change that.

We admit this project isn’t totally new– indeed, it looks like [Jurgen]’s last update was in 2024– but a fast 6502 is just as obsolete today as it was when [Jurgen] started work in 2020. That’s why when [Stephen Walters] sent us the tip (via electronics-lab), we just had to cover it, especially considering the 6502’s golden jubilee.

We also recently featured a 32-bit version of the venerable chip that may be of interest, also on FPGA.

Rackintosh Plus Is The Form Factor Nobody Has Been Waiting For

September 10, 2025 by Tyler August 20 Comments

For all its friendly countenance and award-winning industrial design, there’s one thing the venerable Macintosh Plus can’t do: fit into a 1U rack space. OK, if we’re being honest with ourselves, there are a lot of things a Mac from 1986 can’t do, but the rack space is what [identity4] was focused on when they built the 2025 Rackintosh Plus.

Some folks may have been fooled by this ad to think this was an actual product.

For those of you already sharpening your pitchforks, worry not: [identity4]’s beloved vintage Mac was not disassembled for this project. This rack mount has instead become the home for a spare logic board they had acquired Why? They wanted to use a classic Mac in their studio, and for any more equipment to fit the space, it needed to go into the existing racks. It’s more practical than the motivation we see for a lot of hacks; it’s almost surprising it hasn’t happened before. (We’ve seen Mac Minis in racks, but not the classic hardware.)

Aside from the genuine Apple logic board, the thin rack also contains a BlueSCSI hard drive emulator, a Floppy Emu for SD-card floppy emulator, an RGB-to-HDMI converter to allow System 7 to shine on modern monitors, and of course a Mean Well power supply to keep everything running.The Floppy Emu required a little light surgery to move the screen so it would fit inside the low-profile rack. [identity4] also broke out the keyboard and mouse connectors to the front of the rack, but all other connectors stayed on the logic board at the rear.

Sound is handled by a single 8-ohm speaker that lives inside the rack mount, because even if the Rackintosh can now fit into a 1U space, it still can’t do stereo sound…or anything else a Macintosh Plus with 4 MB of RAM couldn’t do. Still, it’s a lovely hack. and the vintage-style advertisement was an excellent touch.

Now they just need the right monochrome display.

Was Action! The Best 8-Bit Language?

September 9, 2025 by Tyler August 22 Comments

Most people’s memories of programming in the 8-bit era revolve around BASIC, and not without reason. Most of the time, it was all we had. On the other hand, there were other options if you sought them out, and [Paul Lefebvre] makes the case that Goto10Retro that Action! was the best of them.

The limits of BASIC as an interpreted language are well-enough known that we needn’t go over them here. C and Pascal were available for some home computers in the 1980s, and programs written in those languages ran well, but compiling them? That was by no means guaranteed.

The text editor. Unusual for Atari at the time, it allowed scrolling along a line of greater than 40 char.

For those who lived on the Atari side of the fence, the Action! language provided a powerful alternative. Released by Optimized Systems Software in 1983, Action! was heavily optimized for the 6502, to the point that compiling and running simple programs with “C” and “R” felt “hardly slower” than typing RUN in BASIC. That’s what [Paul] writes, anyway, but it’s a claim that almost has to be seen to be believed.

You didn’t just get a compiler for your money when you bought Action!, though. The cartridge came with a capable text editor, simple shell, and even a primitive debugger. (Plus, of course, a hefty manual.) It’s the closest thing you’d find to an IDE on a computer of that class in that era, and it all fit on a 16 kB cartridge. There was apparently also a disk release, since the disk image is available online.

Unfortunately for those of us in Camp Commodore, the planned C-64 port never materialized, so we missed out on this language. Luckily our 64-bit supercomputers can easily emulate Atari 8-bit hardware and we can see what all the fuss was about. Heck, even our microcontrollers can do it.

Retrotechtacular: The Noisy Home Computer From 1967

September 8, 2025 by Al Williams 22 Comments

[Rex Malik] didn’t need an alarm clock. That’s because he had one of two “home computer terminals” next to his bed and, as you can see in the video below, it made quite a racket. The terminal looks like an ASR33 with some modifications. In 1967, it was quite a novelty and, of course, it didn’t have any real processing power. It connected to an “invisible brain” ten miles away.

What do you do with a computer in 1967? Well, it looks like you could trade stocks. It also apparently managed his shopping list and calendar. His young son also learned some letters and numbers. We’d love to hear from the young [Mr. Malik] today to find out what kind of computer he’s using now.

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The Sixteen-Year Odyssey To Finally Emulate The Pioneer LaserActive Console

September 8, 2025 by Maya Posch 16 Comments

The 1993 Pioneer LaserActive certainly ranks high on the list of obscure video games. It was an odd duck; it used both a LaserDisc for data storage and provided compatibility with a range of existing video game consoles. Due to the rarity and complexity of this system, emulating it has proven to be a challenge. The Ares emulator version 146 is the first to officially add support for the LaserActive. You’d expect getting to that point to be a wild journey. It was, and [Read Only Memo] documented the author’s ([Nemesis]) quest to emulate the odd little machine.

The LaserActive had a brief lifespan, being discontinued in 1996 after about 10,000 units sold. Its gimmick was that in addition to playing regular LaserDiscs and CDs, it could also use expansion modules (called PACs) to support games for other consoles, including the Sega Genesis and the NEC TurboGrafx-16. You could also get PACs for karaoke or to connect to a computer.

By itself, that doesn’t seem too complex, but its LaserDisc-ROM (LD-ROM) format was tough. The Mega LD variation also presented a challenge. The LD-ROMs stored entire games (up to 540 MB) that were unique to the LaserActive. Finding a way to reliably dump the data stored on these LD-ROMs was a major issue. Not to mention figuring out how the PAC communicates with the rest of the LaserActive system. Then there’s the unique port of Myst to the LaserActive, which isn’t a digital game so much as an interactive analog video experience, which made capturing it a complete nightmare.

With that complete, another part of gaming history has finally been preserved and kept playable. Sure, we have plenty of Game Boy emulators. Even tiny computers now are powerful enough to do a good job emulating the systems of yesterday.

A photo of two magnetic bubble memories installed in a circuit board

Scott Baker’s Magnetic Bubble Memory Mega-Post

September 5, 2025 by John Elliot V 11 Comments

Over on his blog our hacker [Scott Baker] has a Magnetic Bubble Memory Mega-Post.

If you haven’t heard of magnetic bubble memory before it’s basically obsolete nonvolatile memory. Since the 1970s when it was introduced this type of memory has been outperformed in every dimension including durability, reliability, price, density, performance, and so on. For any given application of bubble memory you will be able to find an alternative technology which is better in many ways. Except if you want some old tech to geek out over, in that case magnetic bubble memory is for you!

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Microsoft BASIC For 6502 Is Now Open Source

September 4, 2025 by Jenny List 29 Comments

An overriding memory for those who used 8-bit machines back in the day was of using BASIC to program them. Without a disk-based operating system as we would know it today, these systems invariably booted into a BASIC interpreter. In the 1970s the foremost supplier of BASIC interpreters was Microsoft, whose BASIC could be found in Commodore and Apple products among many others. Now we can all legally join in the fun, because the software giant has made version 1.1 of Microsoft BASIC for the 6502 open source under an MIT licence.

This version comes from mid-1978, and supports the Commodore PET as well as the KIM-1 and early Apple models. It won’t be the same as the extended versions found in later home computers such as the Commodore 64, but it still provides plenty of opportunities for retrocomputer enthusiasts to experiment. It’s also not entirely new to the community, because it’s a version that has been doing the rounds unofficially for a long time, but now with any licensing worries cleared up. A neat touch can be found in the GitHub repository, with the dates on the files being 48 years ago.

We look forward to seeing what the community does with this new opportunity, and given that the 50-year-old 6502 is very much still with us we expect some real-hardware projects. Meanwhile this isn’t the first time Microsoft has surprised us with an old product.

Header image: Michael Holley, Public domain.