Back fromt he Grave: Commdore 1571 redux (light stays on and the system locks)

  This entry is going to seem familiar at a glance, as the title is nearly identical to a previous entry. Unfortunately this is due to the tragic nature of retro computers in general: parts are inevitably going to fail, even when living an easy life. It's for this reason that both emulation and software preservation are going to start becoming more and more important as time goes on as eventually there simply won't be replacement parts available for many of these machines, and trying to fix ICs at the individual transistor level doesn't seem like it will ever be within the reach of a hobbyist - either in terms of ability or simple practicality.

Back from the Grave: Before you begin

(Originally drafted on January 21, 2018. Blogger just decided not to post it when I asked, for reasons I can't even begin to guess)

Before I get into my new series, I'd like to take a moment to outline some of the tools, equipment and processes that can (and should) be used for people wanting to undertake such things.  Keep in mind that I'm more of an electrics person than electronics, so it's going to be a fairly "simple" list of tools - but don't let that fool you into thinking they can't get many, many jobs done.

Back from the Grave: Apple //e (keyboard repeating and ignoring input)

(Originally drafted on February 17, 2018. Blogger just decided not to post it when I asked, for reasons I can't even begin to guess) 

The Apple II series includes a fairly unusual keyboard  A semi-custom decoder chip feeds the input via a ROM to determine which character code should be sent to a system.  This meant that custom keyboard layouts (such as DVORAK) could easily be implemented by only switching the ROM, and modified or extended characters (such as the extras added to the //e Enhanced and Platinum) could be easily dealt with.

It also offers functional advantages and disadvantages.  On the one hand, a full keyboard matrix meant that every key can be read individually - something only more expensive modern keyboards offer.  On the other hand, the decoder provides no feedback when individual keys are released, so the system only really ever knows what the last key pressed was.  These two aspects combined to make it extremely good for typing, but abysmal as a control method.

Back from the Grave: Atari Lynx II (No power, capacitor leak)

Released just two months after the Nintendo Game Boy, the Atari Lynx had all the makings of a clear winner in the portable console wars of the late 80s before it even began: a more efficient yet still familiar CPU; a backlit, colour display being driven by a 16-bit graphics chip capable of blitting and an extensive array of hardware manipulation; four channel, stereo, digital sound support; and support for up to 16-player gaming through link hardware. On paper, it left Nintendo's offerings for dead.

Unfortunately for Atari, Nintendo had three rather significant counter points in its favour: the Game Boy's launch price was only half that of the Lynx, Nintendo was able to focus on more than one device at a time, and they knew how to run advertising campaigns. Despite its clear shortcomings this meant that the Game Boy would go on to enjoy far more success simply by virtue of market penetration, rather than any actual merits.

Towards the end of the Lynx's lifetime a second model - known as the Lynx II - was released. This version, like modern "slim" consoles, was aimed to reduce costs and power usage, thus improving battery life. But it would prove to be too little too late as Atari would very shortly afterwards shift their focus entirely to the ill-fated Jaguar. This single-minded approach ultimately heralded the end of the Lynx, and of Atari itself as a hardware company when the Jaguar failed to compete with the PlayStation and Saturn.

Back from the Grave: Acorn A4000 (Battery leak, environmental damage)

Despite its obvious performance advantages against much all of the competition, Acorn redesigned its formerly-Archimedes systems to compete on the new battlefront: price. In 1992, this would be realised with the implementation of the ARM250 - an SoC variant of the ARMv2 chip. While raw performance was slightly inferior to the ARMv3 that had been used since 1990, the removal of many discrete components resulted in potentially significant cost savings

Sadly for Acorn this still wasn't enough to bring them to the forefront. By this point in time, Intel's x86 and IBM's PowerPC had basically claimed a duopoly on both the home and professional computer markets. Acorn would go on to continue their efforts to make inroads with the RiscPC but would not manage to gain the notoriety they deserved until the late 2000s.

Back from the Grave: Acorn A3000 (Battery leak)

In 1983, Acorn - already well known for the existing BBC Micro - set about attempting to compete with IBM in the business domain.  After determining that all the existing options were unsuitable they would settle on designing their own processor, unknowingly becoming one of the grandfathers of modern computing. Following successful simulations run in BASIC on a BBC Micro, in 1985 they would produce the first prototype Acorn RISC Machine processors, better known today as ARM processors.

It would be a further 2 years before these processors would see a commercial release, however, as the ARMv2 powering the brand new BBC Archimedes. A dozen or so models were released in all over the next 5 years eventually producing the ARMv3 and perhaps the first ever example of an SoC in a commercial product with the ARM250 variant of the ARMv2.

While their obvious performance advantage over the existing competition, especially in 32-bit scenarios, went largely unnoticed (and largely unused in 2D games), it's fair to say their legacy has well and truly outlived all but x86 when it comes to modern computers.

Back from the Grave: Commodore Plus/4 (kitchen sink)

Following on from the success of the C64, Commodore set about creating a system to replace the ageing VIC-20 - itself still in production - and potentially replacing the C64 itself with something cheaper. The 264 series was born, split into three variants: the largely-unknown-outside-Europe 116, the 16, and the Plus/4. While the former two featured just 16KB of RAM, the latter boasted a full 64KB; plus a 4-programme office suite in ROM (from which it derived its name).

Sadly, for all it did right, it did far too much wrong to make a name for itself. While it had twice the clock speed, more colours to choose from, stereo sound, and even more usable RAM (approximately 60KB was free in BASIC), it cost as much as the established C64, couldn't run the majority of existing Commodore software, had a fractured market due to the 16KB variants, lacked sprite and sound modulation capabilities, and inexplicably changed nearly every external interface to one that was physically incompatible with existing peripherals.

The entire 264 line was discontinued in 1985 - the year after its introduction.