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22 Articles

Retro ISA Card Means Old, Slow Computers No Longer Need Old, Heavy Monitors

May 18, 2021 by 66 Comments

One thing about vintage computers is that they depend greatly on whether or not one can plug a compatible monitor into them. That’s what’s behind [Tube Time]’s Graphics Gremlin, a modern-design retro ISA video card that uses an FPGA to act just like a vintage MDA or CGA video card on the input end, but provides a VGA port for more modern display output options. (Actually, there is also an RGBI connector and a composite video out, but the VGA is probably the most broadly useful.)

Handy silkscreen labels make everything crystal clear. Click to enlarge.

Why bother making a new device to emulate an old ISA video card when actual vintage video cards are still plentiful? Because availability of the old cards isn’t the bottleneck. The trouble is that MDA or CGA monitors just aren’t as easy to come across as they once were, and irreplaceable vintage monitors that do still exist risk getting smashed during shipping. Luckily, VGA monitors (or at least converters that accept VGA input) are far more plentiful.

The board’s design files and assembly notes are all on the project’s GitHub repository along with plenty of thoughtful detail about both assembly and troubleshooting, and the Verilog code has its own document. The Graphics Gremlin is still under development, but you can also watch for the latest on [Tube Time]’s Twitter feed.

Thanks to [NoxiousPluK] for the tip!

Was Novell’s NE2000 Really That Bad?

April 24, 2021 by 42 Comments

If you used almost any form of networked PC in the late 1980s or the 1990s, the chances are that you will at some point have encountered the Novell NE2000 network card. This 16-bit ISA card became a de facto standard for 16-bit network cards, such that very few “NE2000” cards were the real thing. A host of clones filled the market, some of which followed the spec of the original rather loosely. It’s something [Michal Necasek] examines as he takes the reader through the history of the NE2000 and why it gained something of a bad reputation. An interesting read for ’90s PC veterans who battled with dodgy Windows 3.1 network drivers.

The Novell line of network cards were not a primary product of the network server OS company but an attempt to spur the uptake of networked computers in an age when few machines were supplied from the factory with a network card installed. They were largely an implementation of the reference design for the National Semiconductor DP3890 Ethernet interface chipset, and for simplicity of interfacing and drivers they used an I/O mapped interface rather than DMA. The problem with the NE2000 wasn’t the card itself which would work with any NE2000 driver, but the host of “NE2000 compatible” cards that appeared over the decade as that magic phrase became a key selling point at the bottom end of the market. Sure they might contain a DP3890 or its clones, but even minor differences in behaviour would cause them not to work with all drivers, and thus they gained a bad name. The piece reveals the original card as one that might have been slow and outdated towards the end of its reign as a standard card, but maybe one not deserving of the ire directed at it.

If ancient networking kit is your thing, we’ve got some far more obscure stuff to show you.

Retro Recreations Hack Chat With Tube Time

March 15, 2021 by 2 Comments

Join us on Wednesday, March 17 at noon Pacific for the Retro Recreations Hack Chat with Tube Time!

join-hack-chatNostalgia seems to be an inevitable consequence of progress. Advance any field far enough into the future, and eventually someone will look back with misty eyes and fond memories of the good old days and start the process of turning what would qualify as junk under normal conditions into highly desirable collectibles.

In some ways, those who have been bitten by the computer nostalgia bug are lucky, since the sheer number of artifacts produced during their period of interest is likely to be pretty high, making getting gear to lovingly restore relatively easy. But even products produced in their millions can eventually get difficult to find, especially once they get snapped up by eager collectors, leaving the rest to make do or do without.

Of course, if you’re as resourceful as Tube Time is, there’s another alternative: build your own retro recreations. He has embarked on some pretty intense builds to recapture a little of what early computer enthusiasts went through trying to build useful machines. He has built replicas of early PC sound cards, like an ISA-bus AdLib card, its MCA equivalent, and the “Snark Barker”— or is it the “Snood Bloober”? — which bears an uncanny resemblance to the classic Sound Blaster card from the 1980s.

Tube Time will join us for the Hack Chat this week to answer questions about all his retro recreations, including his newest work on a retro video card. Be sure to bring your questions on retro rebuilds, reverse engineering, and general computer nostalgia to the chat.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 17 at 12:00 PM Pacific time. If time zones have you tied up, 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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ISASTM Runs Vintage Cards Over USB

October 16, 2020 by 25 Comments

The ISA bus is a relic of the distant past, and no longer supported by the PC mainstream. Outside of retro fanatics and likely some long-term industrial users, it’s all but forgotten. That hasn’t stopped [Manawyrm] from hacking away, however, and she’s developed a nifty adapter for the modern era.

Still in its early stages of development, the ISASTM is a ISA-over-USB adapter that allows a modern computer to work with older expansion cards. Running on an STM32H743, and using the microcontroller’s native USB1 interface, the ISASTM card is able to be slotted into a backplane in order to address multiple cards with one adapter. [Manawyrm] demonstrates the hardware by running Monkey Island 1 in the PCem emulator, with sound provided by an AdLib ISA soundcard.

There are some throughput issues, which [Manawyrm] aims to solve by switching to USB2 and making some tweaks and improvements to the code. Regardless, it’s an impressive tool that we imagine could have some use in keeping some legacy hardware alive, too. Incidentally, it’s been a long while since we’ve seen a solid ISA hack around these parts. Video after the break.

Continue reading “ISASTM Runs Vintage Cards Over USB” →

Supercon Keynote: Megan Wachs Breaks Down RISC-V

January 27, 2020 by 17 Comments

The 2019 Hackaday Superconference kicked off with a marvelous, and marvelously geeky, keynote talk on the subject of RISC-V by Dr. Megan Wachs. She is VP of Engineering at SiFive, a company that makes RISC-V processors in silicon, but the talk is a much more general introduction to the RISC-V open instruction-set architecture (ISA) and why you’d care. The short answer to the latter is the same reason you care about any other open standard: it promotes interoperability, reusable toolchains, and will result in us all having access to better and faster CPUs.

The video is embedded below, and it’s absolutely worth a watch. Unfortunately, The video is missing the first few minutes, you can follow along through her slides (PDF) and read through our brief recap below of what fell down the video hole.

Continue reading “Supercon Keynote: Megan Wachs Breaks Down RISC-V” →

RISC-V: Why The ISA Battles Aren’t Over Yet

November 12, 2019 by 39 Comments

A computer processor uses a so-called Instruction Set Architecture to talk with the world outside of its own circuitry. This ISA consists of a number of instructions, which essentially define the functionality of that processor, which explains why so many ISAs still exist today. It’s hard to find that one ISA that works for as many distinct use cases as possible, after all.

A fairly new ISA is RISC-V, the first version of which was created back in 2010 at the University of California, Berkeley. Intended to be a fully open ISA, targeting both students (as a learning tool) and industrial users, it is claimed to incorporate a number of design choices that should make it more attractive for a number of applications.

In this article I’ll take a look behind the marketing to take stock of how exactly RISC-V differs from other open ISAs, including Power, SPARC and MIPS.

Continue reading “RISC-V: Why The ISA Battles Aren’t Over Yet” →

Recovering Data From A Vintage MFM Drive

October 10, 2018 by 53 Comments

Even if you aren’t a vintage computer aficionado, you’re probably aware that older computer hard drives were massive and didn’t hold much data. Imagine a drive that weighs several pounds, and only holds 1/1000th of what today’s cheapest USB flash drives can. But what you might not realize is that if you go back long enough, the drives didn’t just have lower capacity, they utilized fundamentally different technology and relied on protocols which are today little more than historical footnotes.

A case in point is the circa 1984 Modified Frequency Modulation (MFM) drive which [Michał Słomkowski] was tasked with recovering some files from. You can’t just pop this beast into a USB enclosure; copying files from it required an interesting trip down computing’s memory lane, with a sprinkling of modern techniques that are sure to delight hackers who still like to dip their toes into the MS-DOS waters from time to time.

The drive, a MiniScribe 2012, has its own WD1002A-WX1 8-bit ISA controller card. [Michał] is the kind of guy who just so happens to have an ISA-compatible AT motherboard laying around, but he didn’t have the correct cooler for its Pentium processor. He stuck a random heatsink down onto it with a rubber band and set the clock speed as low as possible, which worked well enough to get him through the copying process.

Not wanting to fiddle with floppies, [Michał] then put together a setup which would let him PXE boot MS-DOS 6.22 under Arch Linux. He used PXELINUX, part of the syslinux package, and created an entry for DOS in the configuration file under the pxelinux.cfg directory. He then installed netboot which combines a DHCP and TFTP server into one simple package, and configured it for the MAC address of the AT machine’s 3com 3C905C-TXM network card.

With the hardware and operating system up and running, it was just a matter of getting the files off of the MFM drive and onto something a bit more contemporary. He tried to copy them to a secondary IDE drive, but it seemed there was some kind of conflict as both drives wouldn’t operate at the same time. So he pulled another solution from his bag of tricks: using a USB mass storage device on MS-DOS. By emulating a SCSI drive, he was able to get a standard flash drive plugged into a PCI USB card working, which ultimately dragged these ~35 year old files kicking and screaming into the 21st century.

We love keeping old hardware alive here at Hackaday, and documented methods to not only PXE boot DOS but use USB storage devices when you get it up and running will hopefully inspire some more hackers to blow the dust off that old 386 in the attic.