The Intel 8008

Introduced in April 1972, only five months after the landmark 4004, the 8008 helped to establish microprocessors as a new business avenue for Intel, which at the time was primarily a memory company.

Key Takeaways

  • The Intel 8008 was the first 8-bit programmable microprocessor and only the second microprocessor from Intel.

  • The 8008 was initially developed as part of a contract project for another company, but its versatile capabilities led it to succeed as a standalone product.

author-image

By

The Intel 8008 was the world’s first 8-bit programmable microprocessor and only the second microprocessor from Intel. Introduced in April 1972, only five months after Intel had introduced the first programmable microprocessor, the 4-bit 4004, the 8008 had been developed on a separate track and had very different specifications. It featured 50 percent more transistors, eight times the clock speed and was capable of data/character manipulation where the 4004 could only handle arithmetic, allowing the 8008 a much broader range of applications than its predecessor. However, for all its capabilities, the 8008’s greatest contribution, to both Intel and the world, might have been the role it played in cementing the future of microprocessor development and production as a business avenue, which paved the way for the modern computer age.

Photograph of the 8008 Microprocessor, April 1972

The origins of the 8008 lay in a contract project Intel pursued with Computer Terminal Corporation (CTC, today known as Datapoint). In December 1969, Intel engineer Stan Mazor and a representative of CTC met to discuss options for the logic chipset to power a new CTC business terminal. Mazor, who had been working with Ted Hoff on the development of the 4004, proposed that a one-chip programmable microprocessor might be less cumbersome and ultimately more cost effective that building a custom logic chipset. Such a chip would need to be much more powerful than the 4004 to handle the applications it was intended for, but the concept seemed sound. CTC agreed and development work began on the chip, which at the time was known as the 1201.

The CTC deal would ultimately fall through, but by that time the notion of an 8-bit microprocessor was already attracting interest from other parties. After Seiko expressed a serious desire to use the 1201 to power a desktop calculator in early 1971, Intel decided to continue developing the device as a standalone product. Intel was so confident in the product’s market possibilities that it didn’t even charge CTC for the development work it had done, instead wanting only the commercial rights to finish and sell the chip on its own.

The finished product would be renamed the 8008 to create a sense of continuity with the 4004, and indeed there was a conceptual continuity in the two devices’ developments. Three of the 8008’s chief designers, Ted Hoff, Stan Mazor and Federico Faggin, were also crucial to the 4004. (A fourth designer, Hal Feeney, was new to Intel when he joined the 8008 team but was very much invested in the development of programmable logic in semiconductors.) Because of their collective efforts, upon its release “the 8008 earned some of the best reviews of Intel’s brief history,” according to one prominent tech historian.

Looking back, the wisdom of Intel’s decision to continue pursuing microprocessor development is clear, but in 1971 it took vision and courage. After all, Intel had been founded only three years earlier as a memory company, and the commercial possibilities of the microprocessor weren’t yet clear. Both the programmable processors it was developing had grown out of contract projects that didn’t work out — the 4004 for Japanese calculator company Busicom and the 8008 for CTC — and neither was powerful enough to reveal the microprocessor’s true potential. Many customers would understandably be reluctant to incur the expenses associated with a new, unproven technology — it would take time and resources to convince them of the technology’s net benefits, and then more time and resources to help them implement it. Even if Intel’s entry into microprocessors succeeded, it might wind up hurting the company’s core business if mainframe manufacturers who bought Intel’s memory devices came to see the company as competition in the computing business. In all, the microprocessor could easily have been written off as a technical marvel with limited commercial applications.

Instead, Intel’s decision to pursue the development of 8008 even before it had released the 4004 would help establish a foothold for programmable microprocessors and thus pave the way for their modern-day proliferation. The two chips worked together complementarily in demonstrating the new device’s potential: the 4004 introduced the world to a radically new approach to logic programming, while the 8008 offered more capabilities and established that the 4004 was not simply a flash in the pan. Ed Gelbach, who was crucial to the marketing of the microprocessor concept, later recalled:

“[T]he customers were very interested in it. We would get more requests to talk about it. Nobody wanted to talk much about memories. They understood the memory sequence was going to go from one K to two K to eight K, whatever it was, but the microprocessor tickled the imagination of all of the engineers. Every customer that we ever had for whatever product always wanted to talk microprocessors … We used to push it that if you don’t understand it, you’re gonna be left out. It was really clear that this is the next generation.”

Intel’s product seminars were so heavily attended the company began charging for them, and the widespread interest in the 4004 and the 8008 translated into more than enough design wins to prove the staying power of the microprocessor.

Intel 8008 Microprocessor

The 4004 and 8008’s primary commercial appeal was for embedded control applications in instruments rather than general purpose computers. However, Stan Mazor recalled that it didn’t take developers long to learn that they could use Intel’s microprocessor development tools — which Intel offered as design aids — to create rudimentary PCs based on Intel’s microprocessors, and that doing so was often preferable to purchasing a mainframe:

“We even had customers who would tell us that if they wanted to buy a computer in their company, it was a really big deal. They had to have permission from their ‘computer Czar’ but they could buy [an Intel] development system and they could quote, use it as a computer. That was an easier thing for them to do regardless of the price.”

With the success of the 8008 validating and building on the success of the 4004, Intel moved on to its next chip, the 8080, which did much more to realize the full potential of the microprocessor to provide small, low-cost CPUs in general purpose computers. From that point on, microprocessors have become an increasingly essential component of modern electronics, handling everything from toasters to supercomputers, and more broadly are understood to be a basic component of modern life. That transformation began with a small team at Intel who saw the long-term potential of a revolutionary idea and committed themselves to realizing it.