IBM Archive

IBM open sources Power chip instruction set

It has been a long time coming, and it might have been better if this had been done a decade ago. But with a big injection of open source spirit from its acquisition of Red Hat, IBM is finally taking the next step and open sourcing the instruction set architecture of its Power family of processors. Opening up architectures that have fallen out of favour seems to be all the rage these days. Good news, of course, but a tad late.

The hard way to recover the IBM 5100 non-executable ROS

The few times I’ve had the lid off of my 5100 have all been anxious moments, as I have no idea where I’d find replacements for any of the ICs or SLT modules inside the machine. I resolved early on that my recovery of the 5100’s non-executable ROS – the ROS that contains the programming for the 5100’s BASIC and APL interpreters – would be as minimally-invasive as possible. In accomplishing this recovery I may have used more compute than all the IBM 5100s ever built have carried out over the past 44 years.

IBM 360 Model 20 rescue and restoration

In late April of 2019 Adam Bradley and Chris Blackburn were sitting in a pub on a Monday night when Chris happened across a somewhat unusual eBay listing for an IBM 360 Model 20. This eBay listing was unusual mainly because it didn’t actually list the computer as an IBM 360, but rather as an “seltene Anlage “Puma Computer IBM 2020” which roughly translates from German into “rare plant “Puma Computer IBM 2020”. Amazing story.

Iconic consoles of the IBM System/360 mainframes

The IBM System/360 was a groundbreaking family of mainframe computers announced on April 7, 1964. Designing the System/360 was an extremely risky “bet-the-company” project for IBM, costing over $5 billion. Although the project ran into severe problems, especially with the software, it was a huge success, one of the top three business accomplishments of all time. System/360 set the direction of the computer industry for decades and popularized features such as the byte, 32-bit words, microcode, and standardized interfaces. The S/360 architecture was so successful that it is still supported by IBM’s latest z/Architecture mainframes, 55 years later. Although the S/360 models shared a common architecture, internally they were completely different to support the wide range of cost and performance levels. Low-end models used simple hardware and an 8-bit datapath while advanced models used features such as wide datapaths, fast semiconductor registers, out-of-order instruction execution, and caches. These differences were reflected in the distinctive front panels of these computers, covered with lights and switches. This article describes the various S/360 models and how to identify them from the front panels. I’ll start with the Model 30, a popular low-end system, and then go through the remaining models in order. Conveniently IBM assigned model numbers rationally, with the size and performance increasing with the model number, from the stripped-down but popular Model 20 to the high-performance Model 195. This is an incredibly detailed article on this – relatively speaking – arcane topic, filled with beautiful photography. A delight to read.

Decoding photographs of the IBM 5100’s Executable ROS

Use elementary image processing and machine learning techniques to decode images of a computer screen showing hexadecimal digits. The data in these images are ROM contents from an interesting old computer. The IBM 5100 is an early personal computer (ostensibly portable at 24 kg). Depending on customer-selected options, a 5100 could have interactive programming environments for APL and BASIC built into its ROM. Or, if you prefer, its ROS (“read-only storage”), which seems to have been the IBM-favoured term. The youngest 5100s are a bit over 40 at time of writing, and some accounts online suggest that the ROS devices are no longer dependable. This notebook is part of an effort to back up the entire IBM 5100 ROS to modern media. Specifically, this notebook contains code that analyses screenshots (that is, photographs taken with a camera) containing 512-byte portions of the “Executable ROS”—the ROS containing the native PALM code. That sure is one way to perform computer archeology and keep an old technology alive for posterity.

How IBM became the poster child of operating system failure during the ’90s

In the early 1990s, we had no idea where the computer industry was going, what the next generation would look like, or even what the driving factor would be. All the developers back then knew is that the operating systems available in server rooms or on desktop computers simply weren’t good enough, and that the next generation needed to be better—a lot better. This was easier said than done, but this problem for some reason seemed to rack the brains of one company more than any other: IBM. Throughout the decade, the company was associated with more overwrought thinking about operating systems than any other, with little to show for it in the end. The problem? It might have gotten caught up in kernel madness. Today’s Tedium explains IBM’s odd operating system fixation, and the belly flops it created. I personally really loved using OS/2 over the past ten years or so. There’s something quite elegant and appealing about the operating system, and I consider it the best way to run Windows 3.x software there is – it’s entirely built-in. The world would’ve been a very different place had IBM managed to take the operating system crown for the PC industry – or the Mac, for that matter, through Talingent.

Getting an IBM AS/400 midrange computer on the internet

Recently I’ve gotten a hold of an old IBM mid-range computer, an AS/400 150. This is an 1997 server very much aimed at businesses, pay-rolling, inventory management and such. It can be used as a multi user system, with users logging in via a terminal. The operating system it runs is OS/400 and that is also the only OS it can run, no Linux available for this system. Of course it comes with all the fun programming languages like COBOL and RPG, all the business classics. It’s compatible with the IBM system/36, so any programs made for an 80’s S/36 machine run without problems on the AS/400 machines. It also looks very much 90s, though I personally like the cover at the back, hiding all ports. Stories like these are always great reads. This is the kind of hardware I eventually want to collect and play around with once I have the space to do so.

The IBM z14 microprocessor and system control design

Archaic to most people, IBM mainframes play a pivotal role in our everyday life. Behind the scenes, these state-of-the-art machines process billions of transactions every day. Announced in July of last year, IBM's latest mainframe is the z14, succeeding the z13 which launched back in 2015.

Earlier this year at the 65th International Solid-State Circuits Conference (ISSCC) in San Francisco IBM presented some of the architectural changes between the z13 and z14. The paper was presented by Christopher Berry, a Senior Technical Staff Member for the IBM Systems Hardware Development Team. Mr. Berry led the z14 physical design execution.

IBM ThinkPad Power Series 850

So I learned something new today. Back in the early and mid-90s, IBM tried to build a PC-like platform and ecosystem around its PowerPC processor. They called it the PowerPC Reference Platform, or PReP, and with it, you could build what were effectively PC clones with PowerPC processors, ready to run a number of operating systems, including AIX, Windows NT, OS/2, and Apple's failed Taligent project. None of this is news to me.

What is news to me, however, is that aside from a number of desktop PReP machines, IBM also developed and sold a number of PReP laptops under the ThinkPad brand.

Sometime in 1994, IBM started working on a prototype mobile system named Woodfield and designated as type 6020. Very little is known about this system; it was never officially announced or sold. On June 19, 1995, IBM announced the ThinkPad 850 and 820 (announcement letters 195-178 and 195-179, respectively) with a planned availability date of July 24, 1995. The ThinkPad 820 designation was type 6040, code name Wiltwick; the 850 was type 6042, code name Woodfield Prime.

The ThinkPads 820/850 were to be available with no software or with preloaded Windows NT 3.51 or AIX 4.1.3. OS/2 was to come at some unspecified later date, and Solaris 2.5.1 support was announced in February 1996.

The ThinkPad 850 type 6042 came with 16 or 32 MB RAM, 540 or 810 MB hard disk, and 640×480 or 800×600 TFT display.

Definitely an interesting bit of computing history, and I'd love to get my hands on a working model - they pop up on eBay from time to time.

PC-RETRO Motherboard Kit: IBM clone computer

The PC-RETRO Kit Beta (Catalog #PC-RETRO) is a hobby electronics kit for building a faithful reproduction of the classic IBM PC 5150 motherboard from 1982. We have been in development on this new product offering for over 1 year. We started with the original circuit diagrams, as published by IBM in their Technical Reference Manual. These open source circuit diagrams launched the explosion in PC clone products that followed the IBM PC introduction. Reverse engineering the original IBM board was a substantial undertaking, as we found many differences between the 'official' circuit diagrams and actual board construction. Additionally, you can imagine the complexity of trouble-shooting this board and verifying the correct operation! Not to mention the logistical challenge of sourcing the original vintage electronic parts. You will receive all the components to build a PC Motherboard exactly as shown here.

At a mere $189.50 (including international shipping; $149.50 for domestic US customers), this is an absolute steal. I'm very tempted to look into getting this, but my utter lack of even the most basic soldering skills makes me a little nervous. Might be a better idea to get some soldering test kits before attempting a project like this.

Why do I use the IBM Model M keyboard?

The IBM Model M was a keyboard was first released in 1985 as a cheaper successor to the Model F. It's hard to imagine a keyboard more expensive as Model M keyboards cost a bomb even in those days but it's true.

The Model F was based on a very durable capacitive buckling spring but was expensive to produce hence IBM made the Model M with a lower-cost membrane buckling spring model. At the same time, the Model M pioneered the ANSI 101-key layout that is still in use today. This keyboard was also the first one to utilise the PS/2 connector which would go on to be in service for decades.

The Keyboard.

What it’s like to watch an IBM AI successfully debate humans

At a small event in San Francisco last night, IBM hosted two debate club-style discussions between two humans and an AI called "Project Debater". The goal was for the AI to engage in a series of reasoned arguments according to some pretty standard rules of debate: no awareness of the debate topic ahead of time, no pre-canned responses. Each side gave a four-minute introductory speech, a four-minute rebuttal to the other's arguments, and a two-minute closing statement.

Project Debater held its own.

I'd pay so much money to see prominent political leaders debate this machine.

New guts bring new processors, DDR4, USB3 to old ThinkPads

We often see people funneling their passion into keeping beloved devices in operation long past their manufacturer’s intent. These replacement Thinkpad motherboards bring old (yet beloved) Thinkpads a much desired processor upgrade. This is the work of the user on the enthusiast forum 51nb. The hack exemplifies what happens when that passion for legendary gear hits deep electrical expertise and available manufacturing. This isn’t your regular laptop refurbishment, is building something new.

This is incredible. I wish someone could do this with an iBook G4 or a 12.1" PowerBook.

An 8-tube module from a 1954 IBM mainframe examined

IBM's vacuum tube computers of the 1950s were built from pluggable modules, each holding eight tubes and the associated components. I recently came across one of these modules so I studied its circuitry. This particular module implements five contact debouncing circuits, used to clean up input from a key or relay. When you press a key, the metal contacts tend to bounce a bit before closing, so you end up with multiple open/closed signals, rather than a nice, clean signal. The signal needs to be "debounced" to remove the extra transitions before being processed by a computer.

This is so far before my time, it basically looks like 19th century machinery to me. The steps between this module and what we have today blow my mind.

Creating a Christmas card on a vintage IBM 1401 mainframe

I recently came across a challenge to print a holiday greeting card on a vintage computer, so I decided to make a card on a 1960s IBM 1401 mainframe. The IBM 1401 computer was a low-end business mainframe announced in 1959, and went on to become the most popular computer of the mid-1960s, with more than 10,000 systems in use. The 1401's rental price started at $2500 a month (about $20,000 in current dollars), a low price that made it possible for even a medium-sized business to have a computer for payroll, accounting, inventory, and many other tasks. Although the 1401 was an early all-transistorized computer, these weren't silicon transistors - the 1401 used germanium transistors, the technology before silicon. It used magnetic core memory for storage, holding 16,000 characters.

Some people have access to the coolest stuff.

IBM Blue Lightning: world’s fastest 386?

The Blue Lightning CPU is an interesting beast. There is not a whole lot of information about what the processor really is, but it can be pieced together from various scraps of information. Around 1990, IBM needed low-power 32-bit processors with good performance for its portable systems, but no one offered such CPUs yet. IBM licensed the 386SX core from Intel and turned it into the IBM 386SLC processor (SLC reportedly stood for "Super Little Chip").

Fascinating footnote in processor history.

The history of the IBM PC, part two: the DOS empire strikes

Since I abused the first part in Ars' two-parter on the history of the IBM PC for my own selfish purposes, it's only fair to use the publication of part two to actually talk about the subject matter at hand.

In November 1979, Microsoft's frequent partner Seattle Computer Products released a standalone Intel 8086 motherboard for hardcore hobbyists and computer manufacturers looking to experiment with this new and very powerful CPU. The 8086 was closely related to the 8088 that IBM chose for the PC; the latter was a cost-reduced version of the former, an 8-bit/16-bit hybrid chip rather than a pure 16-bit like the 8086.

IBM opted for the less powerful 8088 partly to control costs, but also to allow the use of certain hardware that required the 8-bit external data bus found on the 8088. But perhaps the biggest consideration stemmed, as happens so often, from the marketing department rather than engineering. The 8086 was such a powerful chip that an IBM PC so equipped might convince some customers to choose it in lieu of IBM's own larger systems; IBM wanted to take business from other PC manufacturers, not from their own other divisions.

The IBM PC and its compatibles changed the computing landscape more than any other platform, and to this day it remains the archetype of what people think of when they think of "computer". While the archetypal computer is surely changing into a laptop or even a smartphone, they've got a long way to go before they push the PC out of the collective consciousness as the "default" computer.