Retrocomputing

1678 Articles

The Sinclair Spectrum Gets A Desktop GUI

September 21, 2026 by 19 Comments

Of the popular 1980s 8-bit computers, it’s fair to say that Sinclair’s ZX Spectrum punched above its weight. Sir Clive’s love of squeezing more functionality out of less hardware meant the compromises he made left it less powerful than competitors from Apple, Commodore, or Acorn. Still, the brightest programmers of the age took the little machine to heart and made it do some very impressive things. A desktop GUI, though, surely that would be pushing things too far. Never say never because now [mindbox77] has done it.

ZXdesk is an assembly language program for the 48k Spectrum that gives you something that looks a lot like GEM. It’s got all the things you’d expect from a desktop GUI, with menus, windows, and applications, and we find ourselves suitably impressed.

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Sony’s First Computer

September 18, 2026 by 14 Comments

In 1982, desktop computers were coming into their own, and no clear leaders had emerged. But everyone knew they wanted a piece of the action. This led to, among other things, Sony’s SMC-70, which, frankly, for 1982, was a good-looking, if not oddball, machine. [Tech Tangents] shows the machine off in a recent video.

From the front, the computer looks more-or-less like everything else. But as you move backward, you can see this computer wasn’t another typical entry into the market. One of the things that was the hallmark of successful business computers of the day was expandability. The earlier Altair had the later-titled S100 bus. The IBM PC had the ISA bus. But in both cases, you had to open the box to plug and unplug cards.

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Reconstructing A Pin On A Pin Grid Array Package

September 18, 2026 by 14 Comments

Before moving to land grid array (LGA) packaging whereby each pin on the substrate is just a copper pad, processors commonly used pin grid array (PGA) packaging, including the still highly relevant AMD AM4 socket. With PGA you get a pin soldered onto the copper pad which inserts into the ZIF socket, rather than a fragile pin on the mainboard side. Repairing a damaged PGA pin can be easy if just the pin broke off at the solder joint, or rough if the pad was destroyed, as in the case of this Pentium III CPU that [Bits und Bolts] recently tried to fix.

In the case of something like a ground pin or similarly unimportant pin you can ignore the damage, but in this case it concerned an important pin for this 1.2 GHz Tualatin PIII core, with the damage consisting of a well and truly destroyed pad. The first step to repair the damage is thus to try and rebuild the pad, which was done using solder mask and solder.

Although a PIII-era Celeron CPU is definitely not a high-value CPU, since they have so few and such large pins they do make for useful test subjects when it comes to PGA repair practicing. In this case the affected data pad and pin appears to have been repaired successfully, with it running overclocked to 1.6 GHz and crushing similarly or higher clocked Pentium 4 and AMD Athlon CPUs of the era.

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Every ZX81 Expansion Card You Ever Wanted, All At Once

September 15, 2026 by 25 Comments

The Sinclair ZX81 was a masterpiece of Sir Clive’s desire to get the most out of the least hardware, being about as minimalist as it was possible to get and still be a home computer in 1981. As such it has a keyboard, a Z80, TC and cassette interfaces, 1K of memory, and that was it. There were any number of add-ons for it, but if you were a 1980s kid the chances are you couldn’t afford them. So 45 years later here’s [adam.klotblixt] with OpenSpand — every ZX81 expansion you could think of, all in one!

For a start there’s a RAM expansion. Not the paltry 16K of old, this is user-configurable and has the whole 64K address space minus the ROM to play with. Then there’s SD card storage, hijacking Sinclair BASIC’s LOAD and SAVE commands. It’s got high-res graphics, emulated sound chips, a joystick port, serial ports, a choice of ROMs, and a composite video output. Perhaps the only thing it doesn’t have from back in the day is a printer interface, but we’re sure the serial port could be pressed into service somehow.

It does this all as you might expect these days, with an RP2350 emulating the real parts. The microcontroller disables the onboard RAM and ROM and emulates those too, such is the disparity in power between it and a Z80. We would have done anything for this expansion, back in the day.

The ’81 features here quite often, most recently in a look at Sinclair’s own RAM expansion.

Rosy Retrocomputing

September 14, 2026 by 26 Comments

Most of us are guilty of romanticizing the past. Do you long to be the captain of a tall ship? Just as long as you don’t mind weevils in your food, vitamin deficiencies, and death from an infection when there were no antibiotics. Want to be a medieval knight? Even worse. But surely, retrocomputing is as fun as we remember, right? Turn your computer on, and it comes up with BASIC! Ready for you to write your own programs. None of this GUI foolishness. Of course, this is just another example of rosy retrospection.

Even if you like BASIC or a similar language today, things have changed. You have a nice text editor, a fast computer, debugging tools, along with things like named functions, no line numbers, and modern control structures. None of those things were very common in the 1980s. At least, not on a hobby-grade computer.

Why am I thinking about this? Well, the Hackaday Retrocomputing Challenge is on, and it occurred to me that I wanted to work with some young students in glorious MBASIC on a CP/M machine I built and modified from a Hackaday project. Perfect, right? Many of us started that way, so why shouldn’t they?

But it quickly got old. Even a simple program gets bogged down with GOTOs and GOSUBs to mysterious line numbers. It made me remember the time back in the early 1980s, or maybe even the late 1970s, that I wrote a BASIC preprocessor to scan BASIC with no line numbers and produce proper source, converting labels to line numbers in two passes.

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It’s The Speech Synthesiser You Wanted, For The Computer You Had

September 14, 2026 by 24 Comments

If you had an 8-bit computer in the 1980s and bought a speech synthesiser for it, what you got was invariably an alophone-based synthesiser using the SP0256 or similar. You definitely couldn’t afford DEC’s DECtalk, a high-end standalone speech synthesiser made famous to the masses as the unit used by Stephen Hawking. But now those two worlds can come together, thanks to [Michael Wessel], whose Perfect Paul ][ is a drop-in DECtalk emulator card for the Apple ][.

The PCB includes an RP2040-based Raspberry Pi Pico Zero, plus an I2S DAC and amplifier, speaker, and bus-interface logic. It appears at a set of memory addresses, and interfacing to it is as simple as POKEing DECtalk commands to those addresses. Looking at it, we are guessing this would be easy to bring to other 8-bit era machines.

You can see and hear it sing in the video below the break, and it certainly has the feel of the real thing. We can say with certainty that this would have been a sensation had it appeared back in the early 1980s. This one may be a modern reproduction, but it’s not the first time DECtalk has appeared here; we’ve even brought you a real one.

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A 386 PC For Your RP2350

September 13, 2026 by 28 Comments

We’re at a fortunate moment: microcontrollers available at modest prices are edging into the capability level previously reserved for full-fat systems and can, through emulation, run software beyond classic 8-bit home computers, consoles, or old arcade games. A project we’ve been watching for a while is tiny386, an emulator for ESP32 boards that provides a 386 PC with just enough 486 and 586 instructions enabled to run a modern Linux kernel. Now we’re pleased to note that this platform is making it to the RP2350, with ports for both the FRANK emulation platform and the Waveshare Pi Zero boards. You can now have a 32-bit PC with all the peripherals, including VGA and DVI/HDMI, for the cost of an inexpensive development board.

Having seen tiny386 run on its minimum-spec ESP32 platform, we’ll concede that while it’s usable, it’s not the fastest experience, but the RP2350 port promises better performance. It’s not for a modern full-fat Linux distro, but should work well for running older operating systems such as DOS, or Windows 3.1 and 95, or even a lean Linux setup. This has fascinating potential: while these systems are old, they still have an enormous software library. The idea of useful general-purpose computing, 1990s style, in the palm of the hand, is interesting.

If you’re curious, you can find tiny386 here and the FRANK boards here. Maybe they’re a better route to ’90s fun and games than a 386 laptop.