Arctic Adventures With A Data General Nova II — The Equipment

February 5, 2024 by Chris Lott 49 Comments

As I walked into the huge high bay that was to be my part-time office for the next couple of years, I was greeted by all manner of abandoned equipment haphazardly scattered around the room. As I later learned, this place was a graveyard for old research projects, cast aside to be later gutted for parts or forgotten entirely. This was my first day on the job as a co-op student at the Georgia Tech Engineering Experiment Station (EES, since renamed to GTRI). The engineer who gave me the orientation tour that day pointed to a dusty electronic rack in one corner of the room. Steve said my job would be to bring that old minicomputer back to life. Once running, I would operate it as directed by the radar researchers and scientists in our group. Thus began a journey that resulted in an Arctic adventure two years later.

The Equipment

The computer in question was a Data General (DG) mini computer. DG was founded by former Digital Equipment Corporation (DEC) employees in the 1960s. They introduced the 16-bit Nova computer in 1969 to compete with DEC’s PDP-8. I was gawking at a fully-equipped Nova 2 system which had been introduced in 1975. This machine and its accessories occupied two full racks, with an adjacent printer and a table with a terminal and pen plotter. There was little to no documentation. Just to turn it on, I had to pester engineers until I found one who could teach me the necessary front-panel switch incantation to boot it up. Continue reading “Arctic Adventures With A Data General Nova II — The Equipment” →

Retro-Styled Rasti Laptop Packs Framework Mobo

February 2, 2024 by Tom Nardi 7 Comments

Today, every laptop pretty much looks like every other laptop. Sure you might run into a few different colors and screen sizes out there, but on the whole, all the manufacturers have pretty much agreed on the basic shape and nobody is looking to rock the boat with something different.

Ah, but it wasn’t always so. Before the form factor we all recognize today took over, there were all sorts of interesting variations on the basic portable computer concept. For the Rasti, creator [Penk Chen] definitely took some inspiration from the iconic (and largely unobtanium) GRiD Compass of NASA and Aliens fame. But while its 3D printed case might look like a product of the early 1980s, on the inside, it features a Framework Laptop 13 mainboard using an 11th gen Intel CPU.

In addition to the widescreen 10.4 inch (1600 x 720) QLED display from Waveshare, the Rasti also includes a custom mechanical keyboard that’s actually been spun off into its own project. So even if you can’t swing building the whole Rasti, you could still find yourself tapping away on its vintage-styled input device.

Somewhat unsurprisingly, this isn’t the first time we’ve seen somebody 3D print a computer inspired by the GRiD Compass. The GRIZ Sextant we covered back in 2021 was another triumph that would be the envy of any hacker meetup.

Cheap Hack Gets PCI-X Card Working In PCI Slot

February 1, 2024 by Lewin Day 10 Comments

PCI and PCI-X are not directly compatible, and you’d be forgiven for thinking that means you’re out of luck if you need to use a PCI-X card in a machine that only has basic PCI slots. And yet, that needn’t be the case. As [Peter] shows us, you can work around this with a cheap hacky hack. Our favorite kind!

[Peter] had a PCI-X RAID card that he wanted to use on his Socket 7-based computer. The 3ware 9550SX PCI-X card is 3.3 V only, and doesn’t fit in a typical PCI slot. It’s not compatible mechanically or electrically. Enter a PCI-X riser, which gets around the missing notch that would normally not let the card sit in the slot. Other than that, it just took masking off some pins to avoid damage from the 5 V rail. Throughput is good, too, reportedly sitting at roughly 60-70 MB/s.

The hard part is probably finding a PCI-X riser; PCI-Express stuff is far more common. Few of us need to deal with PCI-X anymore, but if you’re working on some ancient industrial hardware or something, this hack might just save your beans from the roast pot one day.

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How To Build Your Own 16-Bit System-on-Spreadsheet

January 30, 2024 by Maya Posch 17 Comments

Back in the hazy days of the early home computers, many of us would rejoice at running our first BASIC applications, some of us even built our own 8-bit system from a handful of ICs and felt elated the moment the connected LEDs, screen or other output device would show signs of life. It is this kind of excitement that [Inkbox] has managed to bring to the bane of every office worker: spreadsheet programs like Excel. How, you may ask? Why, by implementing a completely functional 16-bit system with 16 general purpose registers, 128 kB of RAM and a 128×128 pixel color display, all inside an Excel spreadsheet, making it conceivably the world’s first System-on-Spreadsheet (SoS).

Perhaps the most tantalizing aspect of this approach is that it provides a very good visual way to indicate what is happening inside the system using color codes and clearly segregated and marked functional elements. Not only can it be programmed manually, but [Inkbox] also created an assembler for the CPU’s ISA – called Excel-ASM16 – all of which is available from the ExcelCPU GitHub project page. The ASM is assembled into a ROM.xlsx file that can then be run by the CPU.xlsx file by triggering the Read ROM button. After this you are confronted with the realization that although it all works, it’s also incredibly slow, at about 2-3 Hz.

Still, with all the elegance of an IMSAI 8080 front panel, we cannot help but give full points for this achievement. Plus it gives many of us something to do during those exceedingly dull meetings where only serious applications like office suites are allowed.

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Bringing An IBM Butterfly Laptop Back From The Dead

January 28, 2024 by Jenny List 8 Comments

Among all the laptops produced over the last few decades, there is one which rises above the rest and which has retained an appeal long after its meager computing resources became obsolete. It’s the IBM 701c, the famous “Butterfly” laptop, whose fold-out keyboard still gives it star quality, and [John Graham-Cumming] has documented the restoration of one from the tattered remains of two scrap examples.

The two laptops in question were someone else’s never-started project, and were in a sorry state. The flexible cables were in poor condition, and the 1990s Ni-MH batteries had leaked and damaged both circuits and case. We were unaware that NiMH leakage could damage plastic, but the parts of these machines were significantly damaged.

One had a working mainboard, the other a working modem card. One keyboard was in pretty bad shape, the other was complete. Of the pair there was a double super twisted nematic (DSTN) display and a more contemporary thin film transistor (TFT) panel. Be thankful if you have never had to use a DSTN laptop, as they were truly awful. From this pile of parts a working machine could be made, and with a new CMOS battery, that cable repair, and a repaint, he was ready. Or at least, as he says, ready for 1995.

This isn’t the first 701c restoration we’ve seen, and within reason, it’s even possible to give them a retro processor upgrade.

A ZX Spectrum Raytracer, In BASIC

January 26, 2024 by Dave Rowntree 12 Comments

[Gabriel Gambetta] knows a few things about ray tracers, being the author of Tiny Raytracer, a raytracer written in just 912 bytes of JavaScript. As a long-time fellow sufferer of the UK-designed ZX Spectrum, could these two love affairs be merged? Could the Tiny Raytracer fit on the ZX Spectrum? In BASIC? The answer is an affirmative, albeit with our beloved speccy’s many limitations.

Ray tracing with only 15 primary colours

The story starts with [Gabriel]’s Computer Graphics From Scratch (CGFS) raytracer algorithms and an existing code base that was ported to the ZX Spectrum’s very limited BASIC dialect, using VSCode for editing, BAS2TAP to generate a tape image file (essentially an audio track) and executed with FUSE. With the toolchain sorted, [Gabriel] adds just enough code to deal with the ray intersection equations of a sphere, and renders a three-sphere scene to a 32×22 pixel colour image, taking a mere 15 minutes of runtime. Fellow sufferers will remember the spectrum had a 32×22 block attribute array (or colour array) with two colour values for foreground and background pixels. Each attribute block contains 8×8 pixels, each of which could be foreground (on) or background (off.) The next stage was then to expand the code to handle pixels as well as blocks, by simply expanding the raytracing to the full 256×176 resolution, and for each block simply determine the two most common colours, and run with those for the whole block. It sort of works, in a very spectrum-esq ‘attribute clash’ kind of fashion.

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Laptop Memory Upgradable Again

January 14, 2024 by Bryan Cockfield 38 Comments

For some computing components, the bottleneck to improved speed and performance hasn’t been power consumption or clock speed but physical space. But a new memory standard may provide all of the power and space-saving benefits of soldered memory modules without losing any upgradability.

The standard is called compression attached memory modules (CAMM) and provides a way for small form factor computers to have upgradable memory without needing dual in-line memory module (DIMM) slots. Unlike DIMM, though, CAMM modules allow for modern high-speed low-power memory to be used and can take advantage of dual-channel properties even if only one memory module is installed. CAMM modules are held in place with small screws, similar to modern M.2 drives, and don’t have the massive footprint of a DIMM slot. This allows laptop manufacturers to save nearly as much space as having soldered memory.

While this won’t solve the problem of computer manufacturers offering only soldered memory as a cash-grab, hopefully, some take the new standard under their wing for those of us who value the upgradability of our hardware. There are of course some problems with newer standards, but right now it seems like the only other viable option is soldered modules or slower, heavier computers. Some may argue that these soldered-on modules can be upgraded in theory, but not without considerable effort.