Intel's 4004 microprocessor calc code brought back to life

From the sweet as a nut files: we've come across a web site that has recreated the original software that ran on Intel's first commercial microprocessor - the 4004, released in 1971.

The story of the 4004's creation is the stuff of legend, and most semiconductor veterans will know the tale. For those who don't, here's a brief recap.

Japanese firm Busicom knocked on a fledgling Intel's door, asking for help creating a series of chips that could power a new line of calculators. Intel's engineers started cranking away on the project but found that creating lots of specialized chips proved too complex and costly. So, Federico Faggin, Ted Hoff, Stan Mazor and Busicom's Masatoshi Shima teamed to craft a more general purpose chip that could be programmed to handle a variety of jobs such as display and printer control.

With what would become the 4004 in hand, Intel talked Busicom into returning the rights to the design as a swap for refunding some development costs and giving Busicom a price cut on the chips.

This let Intel sell its chip - the first commercial microprocessor - to others.

A number of customers experimented with the 4004 and its follow-on, but it was the third generation 8080 put out in 1975 that really kicked Intel's microprocessor biz into overdrive. That chip made its way into hobby computer kits such as the Altair 8800.

(Those interested in more detail on this tale are urged to grab my book on Silicon Valley history or Leslie Berlin's beyond outstanding biography on Intel co-founder Bob Noyce.)

Now you can replicate some of the 4004 magic via a new simulator of the Busicom 141-PF calculator and copy of the code. In addition, you'll find an existing simulator of the actual microprocessor.

There's more on the 4004 at the Intel Museum in Santa Clara. The little museum is located at the front of Intel's headquarters. It's actually quite impressive for a small museum, teaching you a lot about Intel and the chip making process in a few, digestible exhibits. You even find out why the brilliant Noyce almost failed to graduate from college because of a pig. ®