Saturday, September 13, 2025
Refurb weekend: Silicon Graphics Indigo² IMPACT 10000
Wednesday, September 3, 2025
Microsoft makes 6502 BASIC open source
This is, of course, the same BASIC that Gates wanted a percentage of but Jack Tramiel famously refused to budge on the $25,000 one-time fee, claiming "I'm already married." Gates yielded to Tramiel, as most people did then, but I suspect the slight was never forgotten. Not until the 128 did Microsoft officially appear in the credits for Commodore BASIC, and then likely only as a way to push its bona fides as a low-end business computer. Microsoft's source release also includes changes from Commodore's own John Feagans, who rewrote the garbage collection routine, and was the original developer of the Commodore Kernal and later Magic Desk.
The source code is all in one big file (typical for the time) and supports six machine models, the first most likely a vapourware 6502 system never finished by Canadian company Semi-Tech Microelectronics (STM) better known for the CP/M-based Pied Piper, then the Apple II, the Commodore (in this case PET 2001), the Ohio Scientific (OSI) Challenger, the Commodore/MOS KIM-1, and most intriguingly a PDP-10-based simulator written by Paul Allen. The source code, in fact, was cross-assembled on a PDP-10 using MACRO-10, and when assembled for the PDP-10 emulator it actually emits a PDP-10 executable that traps on every instruction into the simulator linked with it — an interesting way of effectively accomplishing threaded code. A similar setup was used for their 8080 emulator. Unfortunately, I don't believe Allen's code has been released anywhere, though I'd love to be proven wrong if people know otherwise. Note that they presently don't even mention the STM port in the Github README, possibly because no one was sure what it did.
While MACRO-10 source for 6502 BASIC has circulated before and been analysed in detail, most notably by Michael Steil, this is nevertheless the first official release where it is truly open-source under the MIT license and Microsoft should be commended for doing so. This also makes it much easier to pull a BASIC up for your own 6502 homebrew system — there's nothing like the original.
Saturday, August 23, 2025
Reverse-engineering Roadsearch Plus, or, roadgeeking with an 8-bit CPU
For computers of this class, devising an optimal highway route becomes an exercise not only in how to encode sufficient map data to a floppy disk, but also performing efficient graph traversal with limited hardware. Today we'll explore Roadsearch-Plus, one of the (if not the) earliest such software — primarily on the Commodore 64, but originating on the Apple II — and at the end "drive" all the way from southern California to British Columbia along US Highway 395, my first long haul expedition, but as it was in 1985. Buckle up while we crack the program's runtime library, extract its database, and (working code included) dive deeply into the quickest ways to go from A to B using a contemporary home computer.
Saturday, August 2, 2025
A real PowerBook: the Macintosh Application Environment on a PA-RISC laptop
Well, no need to strain yourself imagining it. Here's nearly as close as you're gonna get.
In October 1997 you could have bought a PowerBook 3400c running up to a 240MHz PowerPC 603e for $6500 [about $13,000 in 2025 dollars], which was briefly billed as the world's fastest laptop, or you could have bought this monster new to the market, the RDI PrecisionBook running up to a 160MHz (later 180MHz) PA-7300LC starting at $12,000 [$24,000]. Both provided onboard Ethernet, SCSI and CardBus PCMCIA slots. On the other hand, while the 3400c had an internal media bay for either a floppy or CD-ROM, both external options on the PrecisionBook, the PrecisionBook gave you a 1024x768 LCD (versus 800x600 on the 3400c), a bigger keyboard, at least two 2.5" hard disk bays and up to 512MB of RAM (versus 144MB) — and HP-UX.And, through the magic of Apple's official Macintosh Application Environment, you could do anything on it an HP PA-RISC workstation could do and run 68K Mac software on it at the same time. Look at the photograph and see: on our 160MHz unit we've got HP-UX 11.00 CDE running simultaneously with a full Macintosh System 7.5.3 desktop. Yes, only a real Power Mac could run PowerPC software back then, but 68K software was still plentiful and functional. Might this have been a viable option to have your expensive cake and eat it too? We'll find out and run some real apps on it (including that game we must all try running), analyze its performance and technical underpinnings, and uncover an unusual artifact of its history hidden in the executable.
(A shout-out to Paul Weissman, the author and maintainer of the incomparable PA-RISC resource OpenPA.net, who provided helpful insights for this article.)
Monday, July 28, 2025
So I saw this headline
Saturday, June 28, 2025
Refurb weekend: Gremlin Blasto arcade board
However, a few games I played on the Tutor first before I ever played them on an arcade cabinet (Pooyan and Loco-Motion come to mind), and one outlier I never played in the arcade at all. Earlier, when we briefly lived in the Antelope Valley north of Los Angeles, the first computer I got to ever touch (albeit briefly) was a Texas Instruments 99/4A in the third grade classroom. Among other cartridges it had a brisk and zippy arcade conversion called Blasto from Milton Bradley which never got ported to any other system, and it wasn't until after college that I reacquainted myself with the TI version in emulation. I never actually got to put quarters in one.
A shame, because by then we lived on the mean streets of east county San Diego, California — not far, it turns out, from the corporate office of Gremlin Industries where the original arcade incarnation of Blasto was developed (completely unrelated to the later PlayStation game). I spent most of my childhood and got my bachelor's degree in San Diego, and I still consider it my hometown. Decades later I managed to pick up an original service manual for yuks last year, which sat mostly pristine in my collection, but much more recently an actual Blasto logic board based on an 8080A CPU turned up on eBay. After waiting awhile for the seller to cut the crap, they finally posted it at a not totally unreasonable price for a completely untested item, as-was, no returns, with no power supply, no wiring harness and no auxiliary daughterboards. At the end of this article, we'll have it fully playable and wired up to a standard ATX power supply, a composite monitor and off-the-shelf Atari joysticks, and because this board was used for other related games from that era, the process should work with only minor changes on other contemporary Gremlin arcade classics like Blockade, Hustle and Comotion [sic]. It's time for a Refurb Weekend.Saturday, June 21, 2025
See Jane 128 by Arktronics run (featuring Magic Desk, 3-Plus-1 and the Thomson MO5)
I never used Jane myself back in the day, or for that matter any 128 native word processor, and even when we got a 128 I still wrote my term papers in Pocket Writer 64 or Timeworks Word Writer. However, that faulty but repairable Australian Commodore 128DCR I got last Christmas came with a big box of software and in there was a complete copy of Jane 128 along with the data disk the previous owners' family had used. They were delighted when I said I wanted to take a whack at converting their files as a thank you — and along the way we'll take a look at Jane's oddball history, the original Apple II version, the Commodore 128 version and its all-but-unknown port to the French Thomson MO5, plus those other attempts at productivity applications Commodore tried in the mid-1980s.









