First Microprocessor 1201 CPU hurt by Intel focus

I am ready to defend the Datapoint 1201 as the world’s first alphanumeric microprocessor.   Although TI was first able to produce the actual chip in the TMX 1795, Intel management decided it was worth losing Datapoint as a customer over a less risky, simply packaged, 4004 calculator chip .

“Faced with the facts that the logic design of the 8008 was made by Datapoint and its initial chip implementation was covered by a Texas Instrument patent application, Intel conferred on 4004 the status of the first microprocessor.”  – Dan Alroy  chairman of the 1975 IEEE conference.

At the suggestion of Alroy,  Datapoint’s Gus Roche was to attend the 1975 conference and give a speech about his contribution.  On the eve of the convention Roche was killed in a car accident.





Young Bill Gates next to a Datapoint 1800 programmable, stand-alone machine with 60K user RAM, 4K system ROM, and an 8-bit CPU built from a TTL chipset.   In the modern photo the 1800 is replaced by a dual Z80, Intertec Superbrain. 

As far as chips go the TI implementation of the 1201 has recently been rediscovered by Ken Sheriff in his excellent blog post “The first forgotten CPU : TMX 1795″   Unless someone has a “1201” prototype 16-pin version of the 8008 around the 4004 is as close to the first CPU as collectors have been able to come on the Intel side.

While the 4004 was groundbreaking Intel’s management effectively sabotaged the 1201 forcing designers to bow to Datapoint specs.  The specs fit Andy Grove’s 16-pin package design for memory and no one was about to challenge the company package.

Intel’s management was focused on memory chips and viewed the 4004 as just another MOS semiconductor.  When management finally realized the potential of the CPU they needed to buy the rights of the 4004 back from Japanese calculator maker Busicom.

Mostek’s calculator on a chip soon replaced the 4004 in Busicom’s business line while TI went into the calculator business themselves with the TMS100.

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