This is amazing; it's an article from Programmable Logic DesignLine that describes how you can repair an old gaming system by using programmable logic (in the form of a Xilinx CPLD) to emulate a hard-to-replacean obsolete (actually 35 cents each as Kyoorius points out in the comments, but assumed obsolete "for the sake of this project") chip. The author, In Choi, has a great justification for doing this project:

You may be wondering why I did this exercise. Wouldn't it have been easier to buy a video game console from this or even the last decade? I didn't do the design simply to restore the video game - I did it for a number of reasons.

First off, I think logic design is fun (and I'm lucky enough to get paid to do it). Second, I wanted to show that I could create the RLD [retro logic device] to directly replace a failed part. But my main reason for doing the project was to create a methodology with an FPGA to show that there are indeed practical ways to overcome chip obsolescence.

Replacing obsolete video game circuits with Xilinx CPLDs [via Andrew Plumb on twitter]

(Pictured above, a screenshot from the cross-platform ParaJVE Vectrex emulator)

In November of 2000, John Pultorak got to thinking about building a replica of a 60's or 70's era digital computer from scratch. By 2001, he started placing orders for technical documentation and had chosen his target machine, a Block I Apollo Guidance Computer.

Four years later, in September 2004, he had completed a fully functioning replica of the worlds first integrated circuit computer.

In the 1960's, each Apollo moon mission had one AGC in the command module, and a second in the lunar module. These were used by astronauts to collect real-time flight information and control the spacecrafts' navigation and guidance systems. Almost half a century later, John Pultorak has one in his basement, and thanks to his remarkable documentation and collection of reference materials, you can have one in your basement too!

Block I Apollo Guidance Computer (AGC):
How to build one in your basement

As part of the NYU ITP "5in5" event this week, I created the Asterisk File Transfer Protocol. Using the CSound audio programming language, I wrote a PHP script that converts a binary file into an audio WAV file based on the "Kansas City standard", created in 1975, for transferring binary files via audio cassette. However, instead of a cassette, a user can dial my extension on an Asterisk VoIP PBX server and "retrieve" a file (an 8kb jpeg image) at 300 baud over POTS. You can access the file by dialing (212) 796-0729 ext. 160.

In reality, the audio quality of the GSM codec I was limited to by the server probably precludes one from ACTUALLY downloading the file, but it's still fun! If you want to hear a higher-fidelity version of the file you can access it at http://www.menscher.com/itp/blogmedia/aftp.mp3.

Corey posted the source he used to generate the encoded WAV from an image, so you can see the nuts and bolts of using CSound to generate audio data in PHP. It'd be neat to see the decoder half of this, but it's been left as an exercise for the reader.

I have fond memories of saving and loading files from a C64 datasette drive like this, so it's pretty cool to see this sort of thing done in PHP.

The Asterisk File Transfer Protocol

I was recently wondering about what's happened with OpenVMS. Is it still around? Will it run on normal PC hardware?

It turns out there are still a number of VMS devotees and hobbyists out there, and OpenVMS can still be found running not only on hobbyist legacy systems, but also in modern server environments where security, fault-tolerance, and uptime command a high premium over hardware cost and operating system popularity. There's even a freely available hobbyist license for OpenVMS, and you can get the installer media shipped your way for $30.

But what do you run it on if you don't have a VAX or Alpha in your basement? An emulator, of course! The SIMH emulator, created by the Computer History Simulation Project, is capable of emulating a DEC VAX and will run on a Linux, Windows or OS X host machine.

The most difficult thing, from what I've read, is that you need to jump through a number of hoops to get the OpenVMS license and media and the license needs to be renewed yearly. Phillip Wherry wrote a very extensive howto in 2004 that walks you through obtaining the media, building and configuring the SIMH emulator in Linux, and installing OpenVMS on your virtual VAX. If you want to run OpenVMS on Windows or OS X, there are pre-compiled SIMH binaries available for both platforms. The installation process should be the same for whichever host system you use.

Keep in mind that Phillip's howto was written in 2004, and I haven't gotten my OpenVMS hobbyist license yet, so I don't know for sure if there are any gotchas in there. The DECUS user group still seems to be alive and the company that ships the OpenVMS media is still taking orders, which is a pretty good sign. If any readers out there are currently running this setup, please give us an update in the comments. I'm excited to see some of my old DCL scripts running again, so I'm keeping my fingers crossed for good news here.

Running VAX/VMS Under Linux Using SIMH
SIMH VAX Emulator (Linux and Windows)
SIMH binaries for OS X
Encompass - DECUS User Group (Sign up for membership which is required for the license and media
Order Form For OpenVMS Hobbyist CD Media

I've been searching for a way to resurrect my old C64 in all its glory, so I can someday try to introduce my son to programming. The two problems I've run into is that I've lost most of my software, and I've only been able to find a couple of blank floppies. It's only an assumption they will still hold data reliably.

I came across the 64HDD project. It's a promising looking solution to my problem, and looks like it's been actively developed since 1999. Using a DOS PC with a parallel port and a xe1541 cable, pictured above, you can supposedly use the PC as a mass storage device for the C64. Essentially, it turns your PC into a 1541 floppy drive emulator, so you can load and save files on your C64 without trying to track down a working 1541 or disk media.

It also means that you could presumably download a bunch of disk images using your broadband connection, shove them onto a hard disk, and then access everything without having to rifle through piles of disks to find the program you want to run.

Has anyone used this before, or do you have any other recommendations or ideas for bringing a legacy system back to life?

64HDD

InexorableTash wrote an Apple II program in assembly that receives streaming video from a Windows PC over a 115kbps serial connection. Why? So his nautilus avatar could wander about in Second Life on hardware:

For another fun example of new software on the Apple II, check out this video of a Wolfenstein-like game called "Escape from the Homebrew Computer Club 3D". In this game, the Apple is doing all the work, no external PC needed:

Some people might say that this sort of stuff has no real practical purpose, but it seems to me it's an important tribute to personal computing history. It puts the last 30 years of technology in perspective.

I can't help but wonder about what we've got in store for ourselves in the next 30.

Second Life on an Apple II [via BoingBoing]
Escape from the Homebrew Computer Club 3D

Toni Westbrook authored a new C64 game called Shredz64, bringing the best game of all time to the best computing platform of all time:

You can use the real Guitar Hero controller using the PSX64 PS2-to-DB9 converter which Toni also created. This takes the game controller input and maps it to the appropriate up, down, left, right and potentiometer lines for the Commodore.

Shredz64 uses the internal SID audio processor to play any of your favorite SID tunes. In addition to the built-in songs, you can import new SID files and even create new levels by editing note tracks (using the game controller, naturally).

I'm speechless.

Shredz64

It seems like I end up updating my laptop every couple of years, but as cool as new hardware is, sometimes the challenge of finding a new use for the old machine is more interesting. The iNoteBook mod is a classic example, transforming a broken, screenless iBook into a stealth desktop machine.

What's your favorite laptop reuse project? If you've got one, please share in in the comments.

The iNoteBook

Shimon Schocken gave a really interesting Google Tech Talk titled From Nand to Tetris in 12 Steps. In the video, he describes a course where students design a complete virtualized computer system from scratch, building from the humble nand gate, to a functional cpu and memory architecture, to compiler software and an operating system, all culminating in a simple game that runs on the virtual hardware.

The hardware projects are done in a simple hardware description language and a hardware simulator supplied by us. The software projects (assembler, VM, and a compiler for a simple object-based language) can be done in any language, using the APIs and test programs supplied by us. We also build a mini-OS. The result is a GameBoy-like computer, simulated on the student's PC. We start the course (and this talk) by demonstrating some video games running on this computer, e.g. Tetris and Pong.

Building a working computer from Nand gates alone is a thrilling intellectual exercise. It demonstrates the supreme power of recursive ascent, and teaches the students that building computer systems is -- more than anything else -- a triumph of human reasoning.

It looks like most of the course materials are available online. The necessary hardware emulator and simulator software is open source and available from Shimon's website.

CS101 Digital Systems Construction
Video - Building a Modern Computer from First Principles [via Slash7]

For those who haven't yet read, Bruce Sterling's The Hacker Crackdown is an account of the FBI raids on phreakers and crackers during the early 90s, as well as the subsequent formation of the Electronic Frontier Foundation. More importantly, though, the book is a snapshot of internet culture, influencers and influences as the network was beginning to explode into a mainstream platform for communication.

I spent a weekend printing out and reading The Hacker Crackdown on my dot matrix printer when it was released in free, downloadable form in 1994. This sat in a binder on my bookshelf next to a dot-matrix copy of the Linux Network Administrator's Guide. Popular culture was freaked out about "hackers". Digital rights and the protection of intellectual property in the online domain were suddenly hot topics. Meanwhile, real hackers were sitting in front of their computers trying to wrap their heads around free books, open source operating systems, a new platform for global communication, and the text editor and phone jack that could make it all happen for anyone, everywhere.

13 years after it's release as a freely downloadable book, Cory Doctorow is distributing The Hacker Crackdown in podcast format, with Sterling's blessing. So, grab your iPod, download volume 1, and enjoy a seminal piece of internet history.

The Hacker Crackdown Podcast: Part 001 - Link
The Hacker Crackdown: Law and Disorder on the Electronic Frontier - Link

Forget Y2K or the 2007 Daylight Savings Time change, fire up an Apple Lisa, and experience life as it was meant to be lived between 1981 and 1995. Ted Hodges of Low End Mac has a complete writeup on the recently-released Lisa emulator:

I had heard about the Lisa, but I had never had a chance to use the Lisa Office System (LOS). The reason was that the emulator project didn't have a working Lisa emulator, and neither did anyone else - until now.

Ray Arachelian, creator of the Lisa Emulator Project, has finally created a working Lisa emulator.

Hodges' article has a whole mess of screenshots and is an excellent tour of the Lisa and its capabilities. - [via] Link

Related:

• Applefritter on the Lisa emulator - Link
• Lisa Emulator Project - Link

110 FOR I=0 TO 17

120 READ B

130 POKE 1536+I,B

140 NEXT I

200 POKE 512,0:POKE 513,6

210 GRAPHICS 8

220 START=PEEK(560)+256*PEEK(561)

300 POKE START+3,78

310 FOR I=34 TO 98:POKE START+I,14+128:NEXT I

320 POKE START+99,78+128

330 FOR I=102 TO 164:POKE START+I,14+128:NEXT I

400 POKE 54286,192

410 DATA 72,173,198,2,24,105,2,141

420 DATA 10,212,141,198,2,141,26

430 DATA 208,104,64

72         PHA       ; Push A(ccumulator)

173,198,2  LDA 710   ; Load A with playfield 2 color luminance

24         CLC       ; Clear carry

105, 2     ADC #2    ; Add 2

141,10,212 STA WSYNC ; Wait for horizontal sync

141,198,2  STA 710   ; Playfield 2 color luminance

141,26,208 STA $D01A ; Background color register

104        PLA       ; Restore A

64         RTI       ; Return from interrupt

• Retro Gaming Hacks
  
• Display List chapter in Assembly Language Programming for the Atari Computers
  
• 6502 opcodes