A Z80 CPU board built on a piece of prototype board with an edge connector

Designed From Scratch And Fully Handmade: The Modular Coleman Z80 Computer

March 25, 2022 by 34 Comments

While the phrase “I built my own computer” might sound impressive to the uninitiated, anyone with an interest in modern computer hardware knows that there’s really not much to it: buy a case, a motherboard with a CPU, some RAM and peripherals, and you’re pretty much there. What’s way more impressive is designing a complete computer system from the ground up, as [Joshua Coleman] just did when he built the Coleman Z80.

And when we say “from the ground up”, we mean it: everything down to the system bus was hand-drawn by [Joshua] himself. It does share something with modern PCs though: a strictly modular design. There’s a Z80 CPU board, a ROM and RAM board, and even two modules that you could describe as a video card and a sound card. All of these are built on prototyping boards with a 40-pin edge connector and hooked up to a single backplane carrying the main system bus.

Designed as an experimentation platform, the Coleman Z80 has many features that enable testing and debugging, such as an adjustable clock generator and a few beautiful vintage LED displays that show the status of the main bus. Input and output are mainly through a serial link and a 16×2 LCD, but [Joshua] is already planning a keyboard interface and composite video output to give it that proper 1980s home computer vibe. The software is currently limited to a ROM monitor that enables basic I/O commands, but with 256 KB of RAM there’s plenty of potential for writing useful software.

Just as impressive as the design itself is the fact that this was [Joshua]’s first electronic design project; we’ve certainly seen worse first projects! Over the years we’ve featured several cool homebrew Z80 computers, such as a super-minimalistic board, a modular system based on the powerful eZ80, and this cute little one that fits inside an Altoids tin.

Continue reading “Designed From Scratch And Fully Handmade: The Modular Coleman Z80 Computer” →

Custom Macintosh With A Real 486

February 1, 2022 by 12 Comments

Older Apple computers can often be something of a collector’s item, with the oldest fetching an enormously high price in auctions. The ones from the late ’80s and early ’90s don’t sell for quite as much yet, but it’s possible that museums and collectors of the future will one day be clamoring for those as well. For that reason, it’s generally frowned upon to hack or modify original hardware. Luckily, this replica of an Apple Macintosh didn’t harm any original hardware yet still manages to run software on bare metal.

The computer is built around a single-board computer, but this SBC isn’t like the modern ARM machines that have become so ubiquitous. It’s a 133MHz AMD 486 which means that it can run FreeDOS and all of the classic DOS PC games of that era without emulation. In order to run Apple’s legacy operating system, however, it does require the use of the vMac emulator, but the 486 is quite capable of handling the extra layer of abstraction. The computer also sports a real SoundBlaster ISA sound card, uses a microSD card for its hard drive, and uses an 800×600 LCD screen.

As a replica, this computer is remarkably faithful to the original and even though it doesn’t ship with a Motorola 68000 it’s still fun to find retro PC gamers that are able to run their games on original hardware rather than emulation. It reminds us of another retro 486 that is capable of running old games on new hardware without an emulator as well.

Retro Gaming With Retro Joysticks

January 30, 2022 by 12 Comments

One of the biggest reasons for playing older video games on original hardware is that emulators and modern controllers can’t replicate the exact feel of how those games would have been originally experienced. This is true of old PC games as well, so if you want to use your original Sidewinder steering wheel or antique Logitech joystick, you’ll need something like [Necroware]’s GamePort adapter to get them to communicate with modern hardware.

In a time before USB was the standard, the way to connect controllers to PCs was through the GamePort, typically found on the sound card. This has long since disappeared from modern controllers, so the USB interface [Necroware] built relies on an Arduino to do the translating. Specifically, the adapter is designed as a generic adapter for several different analog joysticks, and a series of DIP switches on the adapter select the appropriate mode. Check it out in the video after the break. The adapter is also capable of automatically calibrating the joysticks, which is necessary as the passive components in the controllers often don’t behave the same way now as they did when they were new.

Plenty of us have joysticks and steering wheels from this era stored away somewhere, so if you want to experience Flight Simulator 5.0 like it would have been experienced in 1993, all it takes is an Arduino. And, if you want to run these programs on bare metal rather than in an emulator, it is actually possible to build a new Intel 486 gaming PC, which operates almost exactly like a PC from the 90s would have.

Continue reading “Retro Gaming With Retro Joysticks” →

Old Firewall Reborn As Retro PC

January 17, 2022 by 16 Comments

We like projects where old gear is given a new life. [Splashdust] has a twenty-year old business firewall that’s build like a tank. He cracks it open and finds a complete x86 embedded motherboard inside, and sets off to restore it and turn it into a retro gaming computer (see the video from his Odd & Obsolete YouTube channel below the break).

This business firewall and router box is from a small Swedish firm Clavister, part of their S-Series from the early 2000s. The motherboard appears to be a generic one used in other equipment, and is powered by a VIA Eden ESP 4000 running at 400 MHz. The Eden line of x86 processors were low-power chips targeting embedded applications. The graphics chip is a Twister T by S3 Graphics which was purchased by VIA in 2000. After replacing the electrolytic capacitors, and making a few cables, [Splashdust] pops in a PCI sound card and boots up into Windows 98 from a CF card (we like the compact PCB vise he uses).

In two follow-up videos (here and here), he builds an enclosure (instructions on Thingiverse) and tries out several other operating systems. He was able to get the Tiny Core Linux distribution running with the NetSurf browser, but failed to get Windows 2000 or XP to work. Returning to Windows 98, he tweaks drivers and settings and eventually has a respectable retro-gaming computer for his efforts. The next time you’re cleaning out your junk bins, have a peek inside those pizza-box gadgets first — you may find a similar gem.

Continue reading “Old Firewall Reborn As Retro PC” →

Four Band Digital HF SDR Transceiver Offers High Performance For Only $60

December 8, 2021 by 31 Comments

Amateur radio is a hobby that is often thought of as being exclusive to those with a healthy expendable income. In recent years however, the tides have turned. Cheap microcontrollers and signal generators have helped turned things around, and the $60 USD QDX from QRP Labs goes even further by sending the performance/price ratio through the roof. You can see more details in the video below the break.

The QDX is the creation of [Hans Summers] who is well known for producing affordable high performance amateur radio kits that are focused on low power transmission, called “QRP” in ham radio parlance. What is it? It’s a pocket sized four band (80, 40, 30, 20 Meters) software defined radio (SDR) that is designed to be used with some of the most popular digital radio modes: FT8 and JS8Call, as well as any other FSK based mode such as RTTY. It’s also been tested to work well (and within spec) on 60 Meters.

While classic radios have to be connected to a computer through a special hardware interface, the QDX is designed to connect directly to a computer through a standard USB A>B cable. CAT control, PTT, and Audio are all handled directly by the QDX, and no special interface is needed. While the radio is essentially plug and play, configuration, testing, and troubleshooting can be done by connecting to the QDX’s unique serial console, which among other things contains a text based waterfall. For those who want to run their own SDR receiver, I/Q output can be sent directly through the sound card.

Now for the bad news: due to global chip shortages, the QDX is out of stock at the moment, and there’s no telling when they might start shipping again. QRP Labs is looking to source parts wherever they can to get more of the units made, but of course, so is everyone else right now. Continue reading “Four Band Digital HF SDR Transceiver Offers High Performance For Only $60” →

LEGO Lunar Lander Animatronic Movie Released

March 18, 2021 by 4 Comments

Retired scientist [Mark Howe] spent the last couple months making an animatronic movie featuring his LEGO lunar lander in a video recreation of the Apollo 11 moon landing (also embedded below). [Mark] is not only the producer, but serves as the technical director, set designer, and cameraman as well. He designed and 3D-printed a custom special effects stage for the scene. It gives motion to the LEM using stepper motors, timing belts, pulleys, and a linear guide rod, all hidden inside a discrete upstage tower. He simulates the Lunar regolith using grout, spray adhesive, and a smattering of small rocks.

[Mark] implements the special effects sequencer in an Arduino Nano, and provides sound effects using an Adafruit audio sound board which he loaded up with sound files from the real Apollo 11 landing. Floor strip lighting is provided by an array of Neopixels, and a back-lit Earth is lowered from the fly space for one cut. He made a custom PCB motherboard to hold the Arduino, sound card and motor drivers.

The resulting production is quite impressive. This isn’t [Mark]’s first attempt to relieve the double boredom of both retirement and coronavirus isolation — back in December he produced a similar animatronic movie recreating a Saturn V launch. Thanks to [jhookie55] for the tip.

Continue reading “LEGO Lunar Lander Animatronic Movie Released” →

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.
Continue reading “Retro Recreations Hack Chat With Tube Time” →