retrocomputing

377 Articles

ReactOS: Dipping A Toe In A Millennium-era Open Source Dream

April 27, 2020 by 57 Comments

Do you remember when trying a new OS meant burning a CD? Not merely downloading an ISO and mounting it on a USB drive, but taking a circle of polycarbonate and hoping you didn’t get a buffer underrun as the file you’d spent an entire day downloading was burned onto it. A couple of decades ago that was how we’d take a look at a new Linux distro, and at the time we considered it to be nothing short of incredible that such a thing was possible. One of the ISOs I remember downloading back then was an early version of ReactOS, a project with the lofty aim of creating an open-source equivalent of Windows NT. You might think that in the nearly two decades since then it would have become an irrelevance and its contributors moved on to other work, but no. ReactOS is very much still with us, and indeed has just seen a new release. Version 0.4.13 is the latest in a long line of incremental updates, and remembering those early ReactOS ISOs when I saw their announcement, I thought I’d give it a spin. The result was both a peek at the current state of the project, and a chance to think about the place of a Windows clone in 2020. Continue reading “ReactOS: Dipping A Toe In A Millennium-era Open Source Dream” →

Hacking Apollo Hack Chat

April 20, 2020 by 2 Comments

Join us on Wednesday, April 22 at noon Pacific for the Hacking Apollo Hack Chat with “CuriousMarc” Verdiell, Ken Shirriff, Mike Stewart, and Carl Claunch!

When President Kennedy laid down the gauntlet to a generation of scientists and engineers to land a man on the Moon before the close of the 1960s, he likely had little idea what he was putting in motion. The mission was dauntingly complex, the science was untested, and the engineering was largely untried. Almost everything had to be built from scratch, and entire industries were born just from the technologies that had to be invented to make the dream come true.

Chief among these new fields was computer science, which was barely in its infancy when the 1960s started. By the end of the decade and the close of the Space Race, computers had gone from room-filling, power-guzzling machines to something compact and capable enough to fly men to the Moon and back. The computers that followed all built on the innovations that came about as a result of Apollo, and investigating the computers of the era and finding out what made them tick is an important part of our technological culture.

That’s where this retrocomputing dream team came into play. Together, they’ve poked and prodded at every bit of hardware from the Space Race era they could find, including a genuine Apollo Guidance Computer (AGC) that was rescued from the trash. What’s more, they actually managed to restore it to working condition with a series of epic hacks and sheer force of will.

Marc, Ken, Mike, and Carl will stop by the Hack Chat to talk about everything that went into getting the AGC working again, along with anything else that pops up. Come ready to have your Apollo-era hardware itches scratched by the people who’ve been inside a lot of it, and who have seen first-hand what it took to make it to the Moon and back.

join-hack-chatOur Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, April 22 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

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A NES Motherboard For The Open Source Generation

March 22, 2020 by 36 Comments

As the original hardware from the golden era of 8-bit computer gaming becomes a bit long in the tooth, keeping it alive has become something of a concern for enthusiasts. There have been a succession of remanufactured parts for many of the major platforms of the day, and now thanks to [Redherring32] it’s the turn of the NES console.

The OpenTendo is a completely open-source replacement for an original front-loading Nintendo Entertainment System motherboard, using both original or after-market Nintendo CPU and PPU chips, and other still readily available components. It doesn’t incorporate Nintendo’s CIC lockout chip — Drew Littrell wrote a great article on how that security feature worked — but if you really need the authenticity there is also the NullCIC project that can simulate that component.

It’s an interesting exercise in reverse engineering as well as a chance to look at the NES at the chip level. Also for Nintendo-heads, it provides all the component footprints and schematic items in KiCAD format. Will many be built? Given that the NES was the best-selling console of its time there should be no shortage of originals to be found, but that in no way invalidates the effort put into this project. There will be NES consoles somewhere running for decades to come because of work such as this, simply remember that you don’t need to blow in the slot to make it work!

Dissecting China-Sourced Vintage HP 1970s ICs: Genuine Or Not?

March 16, 2020 by 10 Comments

While repairing a real-time clock module for a 1970s HP computer that had been damaged by its leaky internal battery, [CuriousMarc] began to suspect that maybe the replacement clock chips which he had sourced from a seller in China were the reason why the module still wasn’t working after the repairs. This led him down the only obvious path: to decap and inspect both the failed original Ti chip and the replacement chip.

The IC in question is the Texas Instruments AC5948N (along with the AC5954N on other boards), which originally saw use in LED watches in the 1970s. HP used this IC in its RTC module, despite it never having been sold publicly. This makes it even more remarkable that a Chinese seller had the parts in stock. As some comments on the YouTube video mention, back then there wasn’t as much secrecy around designs, and it’s possible someone walked out of the factory with one of the masks for this chip.

Whether true or not, as the video (also included after the break) shows, both the original 1970s chip and the China-sourced one look identical. Are they original stock, or later produced from masks that made their way to Asia? We’ll probably never know for sure, but it does provide an exciting opportunity for folk who try to repair vintage equipment.

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The Ohio Scientific 300 Trainer

January 30, 2020 by 48 Comments

In the late 1970s there were a host of companies that dominated the computer market before the introduction of the IBM PC. One of these was Ohio Scientific or OSI. [BradH] has an OSI Model 300 trainer — their first major product — and gives us a peek at it along with some history of the company.

Companies like OSI, Southwest Technical Products, Osborne, Northstar, and PolyMorphic were the second wave after the likes of MITS and IMSAI had opened the personal computer market. Only a few companies like Apple hung on and made it work over the long haul.

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COSMAC ELF Lives Again, In FPGA

January 23, 2020 by 44 Comments

Looking around at the personal computing markets in modern times, there seem to be a lot of choices in the market. In reality, though, almost everything runs on hardware from a very small group of companies, and software is often available across platforms. This wasn’t the case in the personal computing boom of the 70s and 80s, where different computers were wildly different in hardware and even architecture. The Cosmac ELF was one of the more interesting specimens from this era, and this one has been meticulously reproduced on an FPGA.

The original hardware was based on an RCA 1802 microprocessor and had a rudimentary (by today’s standards) set of switches and buttons as the computer’s inputs. It was low cost, even for the time, but was one of the first single-board computers available. This recreation is coded in SpinalHDL and the simplicity of the original hardware makes it relatively easy to understand. The FPGA is cycle-accurate to the original hardware, too, which makes it nearly perfect even without any of the original hardware.

The project’s creator, [Winston] aka [wel97459], found that SpinalHDL made this project fun to work on (and released his code on his GitHub page), and was able to get the code down to just 1500 lines to recreate the original hardware. It’s very impressive, and also an accessible read for anyone interested in some of the more unique computers offered during the early computer renaissance in the 70s.

TRS-80 Clone Uses Modern Parts

January 19, 2020 by 35 Comments

Before RadioShack decided the best business model for an electronics store was to harass its customers into buying overpriced batteries and cellphones, it was a great one-stop shop for most discrete components, knobs, resistors, radio equipment, and even a popular computer. That computer, the TRS-80, is a popular one in the retrocomputing world and if you can’t get original parts to restore one, you can always build your own clone.

This build comes to us from [Glen] aka [glenk] who is known for retrocomputing builds like this classic PET we featured a little over a year ago, and this TRS-80 is his latest project. He really gets into the weeds on the hardware, too. This isn’t an FPGA or Raspberry Pi running a TRS-80 on lookalike hardware. [Glen] has completely redesigned the computer from the ground up using modern CMOS components in order to make a modern, perfectly functional replica of the RadioShack classic.

Because of the level of detail [Glen] goes into, this one is a must-read for anyone interested in computing hardware (as opposed to the software, which you could learn about through a more simple emulator) and retrocomputing in general, and also brings most of us back to a more nostalgic, simpler time where a trip to RadioShack was fun and interesting.

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