Recreating Early Apple Mice For The Modern Era

August 9, 2020 by Tom Nardi 30 Comments

At a time when practical graphical user interfaces were only just becoming a reality on desktop computers, Apple took a leap of faith and released one of the first commercially available mice back in 1983. It was criticized as being little more than a toy back then, but we all know how that particular story ends.

While the Apple G5431 isn’t that first mouse, it’s not too far removed. So much so that [Stephen Arsenault] believed it was worthy of historic preservation. Whether you want to print out a new case to replace a damaged original or try your hand at updating the classic design with modern electronics, his CAD model of this early computer peripheral is available under the Creative Commons license for anyone who wants it.

The model is exceptionally well detailed.

[Stephen] tells us that he was inspired to take on this project after he saw new manufactured cases for the G5431 popping up online, including a variant made out of translucent plastic. Realizing that a product from 1986 is old enough that Apple (probably) isn’t worried about people cloning it, he set out to produce this definitive digital version of the original case components for community use.

With these 3D models available, [Stephen] hopes that others will be inspired to try and modify the iconic design of the G5431. Perhaps by creating a Bluetooth version, or adding the ability to right-click. Considering we’ve already seen custom PCBs for mice, it’s hardly a stretch. We’d love to see somebody take him up on the offer, but even if not, the digital preservation of computer history is always welcome.

An Amiga Sampler 30 Years Later

August 8, 2020 by Jenny List 21 Comments

There was a magic moment for a few years around the end of the 1980s, when home computers were better than professional ones. That’s a mighty grand pronouncement, but it refers to the crop of 16-bit home computers that genuinely were far better than nearly all PCs at the time for multimedia tasks. You could plug a sampler cartridge into your Amiga and be in the dance charts in no time, something which sparked a boom in electronic music creativity. As retrocomputing interest has soared so have the prices of old hardware, and for those still making Amiga music that cart can now be outrageously expensive. it’s something [echolevel] has addressed, with an open-source recreation of an Amiga sampler.

As anyone who peered inside one back int he day will tell you, an Amiga sampler was a very simple device consisting of a commonly-available 8-bit A to D converter, a CMOS switch for right and left samples, and maybe an op-amp preamplifier. This is exactly what he’s produced, save fpr the CMOS switch as he points out that Amiga musicians use mono samples anyway. At its heart is an ADC0820 half-flash ADC chip, and the whole thing is realised on a very retro-looking through-hole PCB.

For a Hackaday scribe with a Technosound Turbo still sitting in a box somewhere it’s a real trip down memory lane. It was a moment of magic to for the first time be able to edit and manipulate audio on a computer, and we’re glad to see that something of those days still lives on. See it in action in the video below the break.

Continue reading “An Amiga Sampler 30 Years Later” →

This Mini Soviet Micro Will Have Astounding Attention To Detail

August 1, 2020 by Jenny List 12 Comments

As the retro craze has gone mainstream, we’ve grown used to seeing “mini” versions of classic hardware, preloaded with a selection of games and ready for a wallow in nostalgia. Unfortunately for fans of the less well known platforms, the only devices to get the mini treatment so far are popular ones such as the Nintendo consoles, or the Commodore 64. This is something [Svofski] is aiming to change for one classic micro, by producing a mini version of the Soviet Vector-06c. And unlike the Commodore with its fake keyboard, this one will work in its entirety and have a fully-functional keyboard.

It’s a build that’s not finished yet. But in this case that’s no bad thing, because such is the extreme attention to detail that you’ll want to stick around and watch it unfold. The electronics will come courtesy of an FPGA recreation of the hardware, while the Vector’s unique keyboard is being recreated in miniature, with keycaps designed to fit a particular Alps switch. These are 3D-printed, painted, and then marked with their decals using stencils carefully etched from copper sheet. Even if you have no interest in the Vector-06c, these techniques could find a place in so many other projects.

The wonderfully ingenious and diverse world of Soviet technology has found its way onto these pages many times over the years, including at least one other microcomputer, and even a supercomputer. If your interests extend behind the Iron Curtain though, you might wish to read our colleague [Voja Antonic]’s account of hacking in Communist Yugoslavia.

Reverse Engineering The Charge Pump Of An 8086 Microprocessor

July 31, 2020 by Dan Maloney 17 Comments

You’d think that the 8086 microprocessor, a 40-year-old chip with a mere 29,000 transistors on board that kicked off the 16-bit PC revolution, would have no more tales left to tell. But as [Ken Shirriff] discovered, reverse engineering the chip from die photos reveals some hidden depths.

The focus of [Ken]’s exploration of the venerable chip is the charge pump, a circuit that he explains was used to provide a bias voltage across the substrate of the chip. Early chips generally took this -5 volt bias voltage from a pin, which meant designers had to provide a bipolar power supply. To reduce the engineering effort needed to incorporate the 8086 into designs, Intel opted for an on-board charge pump to generate the bias voltage. The circuit consists of a ring oscillator made from a trio of inverters, a pair of transistors, and some diodes to act as check valves. By alternately charging a capacitor and switching its polarity relative to the substrate, the needed -5 volt bias is created.

Given the circuit required, it was pretty easy for [Ken] to locate it on the die. The charge pump takes up a relatively huge amount of die space, which speaks to the engineering decisions Intel made when deciding to include it. [Ken] drills down to a very low level on the circuit, with fascinating details on how the MOSFETs were constructed, and why eight transistors were used instead of two diodes. As usual, his die photos are top quality, as are his explanations of what’s going on down inside the silicon.

If you’re somehow just stumbling upon [Ken]’s body of work, you’re in for a real treat. To get you started, you’ll want to check out how he found pi baked into the silicon of the 8087 coprocessor, or perhaps his die-level exploration of different Game Boy audio chips.

Myst ‘Demake’ For The Apple II

July 30, 2020 by Maya Posch 12 Comments

Making certain games run on systems which were never designed to run such games (or any games at all) is a favorite hobby of some, with [deater] being no exception. His latest creation involves porting Myst to the Apple II, or ‘demake’ in his own words. This means taking a game that was released in 1993 for MacOS and later for Windows 3.1 and the original PlayStation, and creating a version that works on an 8-bit system from 1977.

Obviously the graphical fidelity has been turned down some compared to the 1990s version, but at this stage much of the game’s levels have been implemented. For anyone who has ever played the game before, much of the visuals will be instantly recognizable. According to [deater], the game should run on any Apple II/II+/IIe, with at least 48 kB of RAM, but 64 kB needed for sound effects. If a Mockingboard sound card is installed, it will even play the intro theme.

On the project page the (currently) three floppy disks can be downloaded, with the source available on Github. While one is there, one can also check out [deater]’s ‘Another World’ port to the Apple II which we covered last year.

Continue reading “Myst ‘Demake’ For The Apple II” →

Die Photos Reveal Logic From Commodore 128 PLA Chip

July 29, 2020 by Dan Maloney 27 Comments

The 8721 PLA, or programmable logic array, was one of the chips that had to be invented to make the Commodore 128, the last of the 8-bit computers that formed the leading edge of the early PC revolution, a reality. [Johan Grip] got a hold of one of these chips and decided to reverse engineer it, to see what the C-128 designers had in mind back in mid-1980s.

PLAs were the FPGAs of the day, with arrays of AND gates and OR gates that could be connected into complex logic circuits. [Johan]’s investigation started with liberating the 8721 die from its package, for which he used the quick and easy method favored by [CuriousMarc]. The next step was tooling up, as the microscope he was using proved insufficient to the task. Even with a better microscope in hand, [Johan] still found the need to tweak it, adding one of the new high-quality Raspberry Pi cameras and motorizing the stage with some stepper motors and a CNC controller board.

With optics sorted out, he was able to identify all the pads on the die and to find the main gate array areas. Zooming in a little further, he was able to see the connections between the matrices of the AND and OR gates, which makes decoding the logic a relative snap, although the presence of what appears to be an output block with latching functions confounds this somewhat.

The end result is a full Verilog HDL file that reflects the original 8721 logic, which we think is a pretty neat trick. And we’d love it if our own [Bil Herd] could chime in on this; after all, he literally designed the C-128.

Smoking Meat With A Commodore 64

July 27, 2020 by Tom Nardi 27 Comments

When [Deadline] couldn’t find a replacement control module for his Masterbuilt electric smoker, he could have just tossed the thing in the trash. Instead, he decided to come up with his own system to take over for the smoker’s original brain. Basing it around the nearly 40 year old Commodore 64 probably wouldn’t have been our first choice, but it’s hard to argue with the end result.

Connectors to control the smoker’s hardware.

At the most basic level, controlling an electric smoker like this only requires a temperature sensor, a relay to control the heating element, and something to get those two devices talking to each other. But for the best results you’ll also want some kind of a timer, and an easy way to change the target temperature on the fly. Connecting the relay and temperature sensor up to the back of the C64 was easy enough, all he had to do was write the BASIC code to glue it all together.

This hack was made considerably easier thanks to the fact that the Masterbuilt’s original controller interfaced with the smoker by way of a couple relatively well documented connectors. So instead of having to mess with any of the mains voltage electronics, he simply had to bring a wire in the connector high to fire up the smoker’s heating element. This bodes well for anyone looking to replace the controller in a similar smoker, with a C64 or otherwise.

In the past we’ve seen some very impressive custom smoker controllers that look as though they could easily be adapted for use with these commercial units. Though the true smoke aficionados might prefer building the entire thing to their exacting specifications.

Continue reading “Smoking Meat With A Commodore 64” →