History of Processors

The Processor that we all know and use today is relatively young, all things considered. The first general purpose CPU, the Intel 4004, entered the consumer market back in 1971 which marked the start for home computers. Since then, the progress in processor technology has been astronomical and has been following Moore's Law up to this day. However, the engineers at Intel and Motorolla didn't invent the modern CPU out of thin air. Let's have a look through history to see how and where it all began, how it has progressed, where we are at right now, and speculate what we can expect for the future!  

01001100 01100101 01110100 00100111 01110011 00100000 01100101 01111000 01110000 01101100 01101111 01110010 01100101 00100000 01110100 01101000 01100101 00100000 01010000 01110010 01101111 01100011 01100101 01110011 01110011 01101111 01110010 01110011 00100000 01100110 01100001 01101101 01101111 01110101 01110011 00100000 01100110 01101111 01110010 01101101 01110011 00100000 01110100 01101000 01110010 01101111 01110101 01100111 01101000 00100000 01110100 01101001 01101101 01100101 00100001

Hover over Bit or click here to see what he says!

Let's explore the Processors famous forms through time!

 

Vacuum Tubes

Before the invention of transistors in 1947, the first computer had already made its appearance. The Electronic Numerical Integrator and Computer, or simply ENIAC, was the first general purpose computer. The University of Pennsylvania, specifically its Moore School of Electrical Engineering, completed the build in December 1945 just after World War II had finished. Its purpose: making calculations and solving complex numerical problems.   The ENIAC relied on a massive list of components to perform its calculations, the most important one being the 18.000 vacuum tubes which performed the switching task that transistors do nowadays. However, these tubes would burn out fairly often, making them less reliable. The majority of the failures happened when the tubes were warming up or cooling down, the moment when they were under the most thermal stress.     Extra Info about the ENIAC   The first programmers of the ENIAC were a group of six women. In order to make sure the computer would be programmed correctly, they first had to figure out the program on paper. Then the program had to be mapped to the ENIAC itself, which could take weeks, by manipulating a multitude of switches and cable plugs. If you fancy programming, definitely give this online tutorial a look. It shows how to implement a modulo function on an ENIAC simulator which should give an impression of what a program on this computer would look like.  

Look, I may be a smart Byte, but even I don't fully understand this ENIAC program and how it works.. Hats off to these amazing women who stood at the starting line of programming, I am you all eternally grateful! Please, a round of applause for Kathleen McNulty Mauchly Antonelli, Jean Jennings Bartik, Frances (Betty) Snyder Holberton, Marlyn Wescoff Meltzer, Fances Bilas Spence, and Ruth Lichterman Teitelbaum!

  Learn more about Computers using Vacuum Tubes  

From Printed Circuit Boards
To Integraded Circuits

With vacuum tube computers already in use by major universities and government instances, the demand for these mathematical geniuses for the consumer market rose drastically. However, the cost of maintenance and tubes could not realistically be covered by most private individuals or even commercial companies. That is even without taking the sheer size of these computers into consideration. Fortunately, during the 50s, a new type of computer came into the playing field which enabled smaller to mid-sized companies to purchase computing power. Two decades later, a new advancement in processor technology would pave the path for home computing that we all know, love, and use today. At the center of these advancements is the transistor, invented in 1947. This quicker and more power efficient component would dominate the processor industry for years to come.  

Transistors on a Printed Circuit Board

Around the mid 50s, two major companies developed the next generation of computers by replacing the vacuum tubes for transistors. They created modules; printed circuit boards with transistors, resistors, capacitors and other electronic components soldered directly onto them. Each type of module had a specific feature or role within the computer. A system would be made up of these modules and such a system could easily be expanded in functionality, memory, or processing capacity by adding more modules. One of the companies, IBM, even created the IBM Standard Modular System which remained in use with legacy systems well throughout the 70s after the introduction of the IBM 1401 in 1959.   Digital Equipment Corporation was a fierce competitor of IBM at the time. They introduced their first fully transistorised computer, the Programmed Data Processor-1 (or PDP-1), in 1959. This machine became pivotal in computer history. Many applications that we deem the norm today were first created on or for this system. The PDP-1 is the original hardware for:  

Playing the first video game, Spacewar!;

The first text editor;

The first word processor

The first interactive debugger to help programmers find the defects in their code;

The first credible computer chess program;

And many more.

  The PDP-1 also caused a big shift in philosophy of computer design: it was the first commercial computer that focused on the user interaction, rather than just the computing efficiency.   The PDP-1, the IBM 7070, and their successors were very popular among companies. These systems were much smaller than the vacuum tube computers available and more maintenance friendly. However, do not be mistaken, these systems were still large, taking up the space of two refrigerators with ease and weighing up to a metric ton. In hindsight, it is a bit ironic that companies called them minicomputers at the time. However, it did fit their initial description: they were smaller general purpose computers and they were sold at a lower price than a full mainframe, which was still the size of the ENIAC or EDVAC during those days.   

The PDP-1 is famous for being the most important computer that created the hacker culture at MIT. The first reference to malicious hacking came from MITs student newspaper, The Tech, talking about "telephone hackers". Apparently, a few student hackers from MIT were tying up the lines with Harvard, configuring the PDP-1 to make free calls, and accumulating large phone bills.

 

Transistors in an Integrated Circuit

During the continued the development of more minicomputers, a shift in electronic circuit technology happened. Since the late 50s, around the time when the first transistor computer came to market, pioneers like Robert Noyce at Fairchild Semiconductor were experimenting with a new way of creating an electronic circuit; one so tiny, that they cannot be seen by the naked eye. This new technology would be the breakthrough to make computers more affordable and smaller, and, overtime, to our wrists and pockets. Integrated circuits brought a new era of computing technology to us.   So, what is an integrated circuit? The science and technology behind this is very complex, but here is an attempt at a simplified explanation. Integrated circuits are like teeny tiny cities with buildings and roads made in silicon. These buildings could be transistors, resistors, and capacitors with little roads interconnecting them. Lightning travels between and through the buildings, resulting in a miniature full electrical circuit. Essentially, it is the same as the printed circuit boards with the electronic components soldered onto them, but much much much smaller.   Nowadays, we cannot live without this technology. The majority of electronics that we use today have these integrated circuits. It doesn't only apply to processors, it is used for a wide variety of components. Do you play video games using a graphics card? Yep, that has ICs in them. Saving pictures and files to your SSD? You bet that's made of ICs. Cameras, whether on your phone or as a camerabody, also littered with ICs.

Maybe, one day, I will attempt to explain in much more detail how integrated circuits and the technology behind it to make them work. For now, just know that it is a miniature electrical circuit. However, if you want to learn more about it, and don't want to wait for me to tell you, I have a few resources that you might find interesting. The materials are complex, just so you know what you're getting into. Learn more about integraded circuits, the metal-oxide-semiconductor field-effect transistor, the applications of MOSFET in the integrated circuit industry, and ASMLs role in the semiconductor industry.

 

A Timeline of Microprocessors

Since the introduction of the first general purpose microprocessor in 1971 by Integrated Electronics (aka, Intel), processor technology has advanced at a rapid rate. Gordon Moore, one of the founders of Intel, speculated that processors would double their transistor count by every two to three years, increasing in speed and operating capacity with each cycle. This observator was later named after him: Moore's Law. Processor technology hasn't disappointed, and still is mostly adhering to this observation. Hence, to keep track of the microprocessors from history, this timeline highlights the most popular CPUs of the past 50 years.   4-bit Important CPUs: Intel 4004 (1971), Intel 4040 (1974)   The Intel 4004 is generally considered the first general purpose processor that gave rise to the integrated circuit technology. With an astounding 2300 transistors fitted into a 12mm² die, roughly the head of a small nail, having a computer at home suddenly became a possibility. The chip was fairly small and still powerful enough to cater to the users needs of that time. While it wasn't used much in the personal computer sphere, it did show the potential that integrated circuits would provide to make this a reality.The Intel 4040 was released three years later as an improvement upon the Intel 4004. Both these chips were designed by the same person, Federico Faggin, who would design a few more impressive CPUs in the oncoming years.

What was your first Processor or Computer? Let me know in the comments!

8-bit Important CPUs: Intel 8008 (1972), Intel 8080 (1974), Motorola 6800 (1974), MOS 6502 (1975), Zilog Z80 (1976)   Not long after the release of the Intel 4004, the Intel 8008 took the stage as the first consumer grade 8-bit CPU. Originally, this processor was not intended to be released as a stand alone CPU for the market. Computer Terminals Corporation commissioned Intel to create a CPU for their Datapoint 2200, because they didn't have the capacity to design and manufacture processors themselves. However, since the processor didn't meet the requirements, CTC allowed Intel to use the design for themselves. After rebranding it, Intel released the Intel 8008 in 1972. The performance of the chip was dreadful, but it was the first 8-bit processor nonetheless.   The Origin Story of the Intel 8008, the first commercial 8-Bit processor.   From this point forwards, the competition within the processor manufacturing and designing sphere was fierce. New companies would spring up, designs would be used and improved; the same designers sometimes would switch company, or start up their own. Prime examples are people like Federico Faggin and the engineers at Motorola.   Faggin had improved the design of the Intel 8008 massively, bringing the Intel 8080 to the world in 1974. Aside from the improved performance, this processor required fewer support chips in order to run properly in a system. Just after releasing the Intel 8080, Faggin decided to start a new company, Zilog, dedicated to manufacturing microprocessors. After two years, in 1976, he released the Zilog Z80, a processor with an improved design of the Intel 8080, and fully compatible with it as well. The company even made fun of the Intel 8080 in a 2-page advertisement in a magazine. The Zilog Z80 was a hugely successful processor, partially because of its improvements upon the Intel 8080, and partially because it was much cheaper.   Motorola released their first 8-bit processor in 1974 as well, the 6800. However, things weren't all rainbows and sunshine there either. Motorola's Semiconductor Products Division management was overwhelmed with problems showing no interest in business proposals given by their processor engineers. This ultimately lead to a few of them walking off to create MOS Technology. Within a year, MOS Technology released a new processor that, like the Zilog Z80, was much cheaper than its predecessor: the MOS 6502.   The introduction of the Zilog Z80 and the MOS 6502 singlehandedly brought us the home computer revolution in the early 80s. Suddenly, it was possible to have a computer at home for a reasonable price which lead to an enormous boom. The VIC-20 used the MOS 6502 chip, the Apple I & II also featured the MOS 6502; the famous Commodore64 used its improved version, the MOS 6510. Sinclair's ZX81 shipped with the Zilog Z80, making it possible to own a computer for just $99 (equivalent to roughly $320 in 2022 and the Sinclair ZX Spectrum featured the improved Zilog Z80A. However, not only home computers benefitted from the 8-bit CPU. Many of the first gaming consoles started out with these CPUs. The Nintendo NES had a clone of the MOS 6502; the Atari 2600 featured the MOS 6507; and the Sega Master System used the Zilog Z80a.  

Did you know that the WDC 65C02 by Western Design Center is still in active use to this day? This little 8-bit CPU (and its bigger 16-bit brother, the WDC 65C816) protect the lives of many people with embedded heart defibrillation and pacing systems! They consume a small amount of power and are very stable, making them the perfect candidates for healthcare applications. Not only that, many hobbyists love toying with these chips! Just like our writer here, who wants to Build a Computer From Scratch.

  The 8-bit processors have laid a foundation in the computer industry that no other CPU can match to this day. They have started the revolution which gave us the home computer, the gaming console which ultimately has lead to the advancement of the technology as a whole. Without these chunky CPUs, we never would have had smart watches or smartphones. These devices are much faster and smarter than our 8-bit friends, but they wouldn't have existed without them.   Want to learn even more about 8-bit CPUs and Computers? 16-bit Important CPUs: National Semiconductor IMP-16 (1973), National Semiconductor PACE (1974), TI TMS 9900 (1976), Intel 8086 (1978), Intel 8088 (1979), WDC 65C816 (1983)   The first 16-bit CPU was not a single unit; with the first 8-bit CPU released the year prior and the first 4-bit CPU two years prior, the design and technology capabilities to make a 16-bit single chip processor wasn't there yet. Instead, National Semiconductor first opted to create a multi-chip 16-bit processor: the IMP-16 released early in 1973. It consisted of two primary components. The first was one chip called the CROM which stands for Control and ROM; it contained the Control Unit to make sure that the processor performs the instructions in the right order and it had a chunk of Read-Only Memory for storing microcode coming from outside the CPU. Four identical chips called the RALU comprised the second primary component; these chips had 4-bit Registers for storing the input and output of the ALU which did all the calculations based on the instructions it was given from the CROM chip. These four chips worked in parallel to produce a 16-bit output and thus a 16-bit processor.   Almost two years later, in late 1974, National Semiconductor managed to improve on their IMP-16 design and produced the first single chip 16-bit processor; the National Semiconductor Processing and Control Element, or PACE. Soon, other companies followed with their first 16-bit single chip processors. In 1976, Texas Instruments introduced their TMS 9900 which was compatible with their TI-990 line of minicomputers, competing with other companies, like DECs PDP series, which were transitioning from transistor computers to using microprocessors during this time.    

Did you know, the first computer of Dimitris, the founder of WorldAnvil, featured the Intel 80286? Its standard clock was 6MHz and had a turbo up to 12MHz, which was really fast for its time. To give an idea how fast computers are nowadays, the Intel Core i5-13400 (an average Intel Core i5) runs natively on 3.3GHz, which is 500x faster than the 80286s standard clock, and has a turbo up to 4.6GHz. The 80286 had 120.000 transistors, whereas the i5-13400 has 14200 million transistors, that's over 100.000 times more transistors!

  Intel's Extra Peripherals 32-bit Important CPUs: Motorola 68000 series, IBM & Motorola PowerPC 600 series, Intel i386, Intel Pentium series, AMD Athlon series  

Rise of Motorola

Shortly after 16-bit processors were available for consumers to purchase, the first 32-bit CPUs started to appear. One of the most prominent 32-bit processors came from Motorola. Their 8-bit M6800 was hugely popular at the time, but sales were already dimming especially with their fierce cheaper competitors (Zilog Z80 and MOS 6502 primarily) taking over a good chunk of the market. By 1976, Motorola was aware of Intel and Zilog working on a 16-bit CPU, the Intel 8086 and the Z8000 respectively. Instead of trying to compete with them directly in the 16-bit space, the company opted to aim directly for a 32-bit processor to get ahead in the game.   Early on in the development, Motorola abandoned the idea of backwards compatibility with the M6800; they felt that its 8-bit design would be too limiting for a new and innovative 32-bit processor. Their primary goal was winning back computer vendors, such as Apple and AT&T, by immensely improving the performance, aiming for a speed of 1 MIPS. Free from the 8-bit limitations, they presented the world with the Motorola MC68000, otherwise known as the Motorola 68k or the m68k, in 1979.   They were competing directly against the Intel 8088 in the IBM PC. Their m68k powered many systems, such as the iconic Apple Lisa and the Apple Macintosh, the first two systems to run an operating system with a graphical user interface. Starting the early 1990s, the use of the m68k family in systems reduced as the PowerPC family, another 32-bit CPU that was made in collaboration between IBM and Motorola, made its way into new iterations of Apple computers throughout the 90s.  

Did you know that at one point there were more MC68020 processors in embedded equipment than Intel Pentiums in PCs?

  Improvements on the M68k  

Intel and AMD; From Partnership to Competitors

In the meantime, Intel didn't sit still. While they were still primarily riding on the success of their 16-bit processors of the x86 family in the early 80s, they had started the development of a 32-bit version on the same instruction set architecture. Three years after the release of their latest 16-bit CPU, the Intel 80286 in 1982, the company introduced the Intel 80386 which was later renamed to i386. It followed in the footsteps of the Intel 8088, powering many personal desktops and company workstations as well. The i386 was widely adopted, not just in personal computers, but also in embedded systems. The processor, or one of its many derivatives, are common in aerospace technology and electronic musical instruments, among others. Its successor, the i486 from 1989, was the first processor to exceed the 1 million transistors in its CPU die mark.  

Did you know that the i386s production was discontinued in 2007? This chip had been produced for over 20 years! The Linux Kernel supported this chip the longest, up until the very end of 2012.

  Up until this point, Intel had a partnership with AMD and a few other companies, dating back to the early 80s. In order to seal the deal with IBM to put the Intel 8088 in their flagship personal computer, Intel had to accept one important condition; IBM wanted to make sure there was a second-source manufacturer capable of producing the processor. Back in those early days, it was a common practise to license other companies to manufacture and sell components originally designed by another company. This was done to make sure that there would always be someone capable of producing the necessary components, so a popular and profitable product can always be made even when the primary production facility burns down for example. Thus, AMD had the designs of the Intel microprocessors in their databases to be able to make them.   While the processor designs of the early x86 family were licensed, Intel decided not to do this for their new flagship line of CPUs: the Intel Pentium. From 1993 until 2003, the Intel Pentium series sealed the domination of Intel in the personal and business computing market. Ranging from personal desktops to the first laptops; from workstations to the first set of cell- and smartphones; nearly everyone was using Intel microprocessors. Over the course of these 10 years, their CPUs increased in complexity, which is determined by the amount of transistors, and capability, which is determined byt he amount of instructions a CPU can execute per second (aka MIPS), by at least three orders of magnitude.   Intel may have dominated the market during this time, but they still had good competition with IBM and Motorola with their PowerPC line that were powering many of Apple's machines. Furthermore, AMD also wasn't keeping quiet either. Even though they didn't have any licenses for the Intel Pentium series, they still had the previous x86 designs as a blueprint for their new designs. In 1991, just before the release of the Intel Pentium, AMD introduced a new CPU that was compatible with the i386, the Am386, designed by their engineers. From this point, AMD became, and still is, a direct competitor of Intel, forcing the company to innovate and to create better microprocessors. The AMD K5 (1996) and AMD K6 (1997) were the predecessors that had lead the team towards the fastest processor for its time; the iconic Athlon line launched in June 1999 and was for two years the fastest x86 CPU breaking the 1GHz speedbarrier. 64-bit Important CPUs: Intel Pentium 4, AMD Athlon 64, Intel Core Duo, AMD Athlon 64 X2, Intel Core Series   During the early 1990s, a few companies were already experimenting with a 64-bit architecture for their CPUs. The majority of these companies focussed on delivering microprocessors for large servers and workstations in big companies. Digital Equipment Corporation was one of the first to introduce the next generation of server CPUs; DEC unveiled the Alpha 21064 to the world during the 39th International Solid-State Circuits Conferences in mid-February 1992. Five years later, Sun (now known as Oracle) launched the UltraSPARC; and in 1997 IBM released their 64-bit processor, the RS64. Only big corporates had access to purchase these products, since they were specifically designed for workstations and servers which often required significantly more computing power than normal consumers.   Aside from the Nintendo 64, which was the first gaming console to feature a 64-bit CPU (hence the name), these advanced processors were not available to regular customers until much later. Roughly 10 years after DEC introduced the Alpha 21064, the AMD Athlon 64 entered the consumer market, bringing 64-bit microprocessors to the regular desktop. These CPUs were compatible with Intels x86 series, allowing them to run code made for all the previous x86 processors without any performance loss. Since it was capable of that, they called it the x86-64 architecture, or AMD64 architecture. Of course, Intel couldn't stay behind for long in this heated processor market if they wanted to maintain their leading position. Soon after, Intel followed with a near fully compatible 64-bit extension of their x86 instruction set architecture in the fourth generation of the Intel Pentium 4.   The shift to 64-bit microprocessors had an immense effect on the software landscape at the time; especially for Operating Systems. Many of the early operating systems developed a 32-bit and 64-bit version, the latter always capable of running the 32-bit software without any performance issues, partially due to the x86 implementation. The 64-bit OS versions fully utilised the extra capabilities of these new CPUs, two of which stuck out the most and had the most impact. For starters, the registers were now expanded to contain 64-bit data values. Secondly, these new processors also had double the number of general purpose registers, allowing the operating system to store more values inside the processor to calculate things.  

Imagine this: the CPU has a storage space with many shelves next to the calculator. It uses the shelves to store values: the inputs for the calculator and the output. These shelves can hold 32 bits of data. To give you an idea, with 32 bits, 32 zeros and ones, you can create 4,294,967,296 combinations of zeros and ones. These combinations form the letters we see on screens, the logic of things, just everything. You have decided to upgrade your CPU with a new and shiny one that is 64-bits. When you walk into the storage space, you see shelves that can hold 64 bits! 64 zeros and ones, which allow you to create 18,446,744,073,709,551,616 different combinations! Not only that, you even have twice as many shelves as before, meaning you cannot only store more on the shelves, but you also have more space to store other data! Think of all the new possibilities, the resources new programs can use now to do more advanced things!

    Multi-Core Processor Designs? Tell me more!   Since the introduction of multi-core CPUs, AMD and Intel have been racing each other striving for better and faster processors. Both started out with a simple single core processor, and over time they have managed to contain up to 12 or even more physical cores. In more recent years, hyper threading has proved to improve the computing power of processors significantly, by creating two virtual cores in every physical core of the processor. In this race for the best CPU, Intel tends to focus more on achieving high frequencies of the CPU which gives them the leading position in the fastest single core performance. On the other side is AMD, whose processors stand vast at the top in multi-threaded performance, meaning they can do a lot of instructions in parallel.   Do you want to know more about the processor that powers your phone, smartwatch, and even washing machines?
Learn more about ARM processors here!  

Yesterday's Future is Tomorrow's History

  So, what can we expect to change in the processor market in the future? It is hard to say what Research and Development departments at Intel and AMD are focussing on at the moment. From this point forward, it is a guessing game what will become the next big thing in processor space.          

Our Writer looks up to the work done at ASML, if you couldn't tell that already. Maybe we can bully her into.. I mean ask her nicely to explain how lithography works, the process to make computer chips that powers all our electronic devices. That way she gets to learn even more about ASML and we get to learn more stuff too! Let our dear writer know in the comments!