Fable: The Immortal CPU

40 years ago this month a computer was launched which was to revolutionise the computer industry.

The computer stayed in mass production for 16 years.

However, the computer’s CPU is still selling in hundreds of millions of units a year.

Moral: Applications fade but tech lives on.



  1. SecretEuroPatentAgentMan

    The 6502 is indeed immortal and this summer a commemorative 6502 powered badge was made: http://www.sunrise-ev.com/6502.htm

  2. You must be pretty speedy zeitghost, it wasn’t a bad machine. GEC head office recommended it to all their units because one of their businesses was distributing it. Caused a bit of bemusement among the techies.

  3. Thanks Duncan, will do

  4. Motorola eventually tried to fight back the 6502 with their 6809 CPU. The 6809 was a very nice architecture, compared to the 6502 **but** by that time the damage was done. There was an attempt at a mass market a computer based on the 6809 ( Dragon, I believe ) but by then software support was more a major issue than hardware architecture. If Steve Jobs had licensed the parts of the Apple II design as listed above, that would have changed the future of computing platforms, but he opted for a closed architecture instead, maybe correctly or not ( support for an open architecture at that time would have taken tremendous effort and committment ) so things stayed pretty much that way until the IBM PC which unwittingly became an open standard ( I think IBM didn’t quite envisage it turning out that way ) by publishing much treasured technical reference manuals including schematics of the PC and it’s support expansion cards and BIOS listing in assembler. Goodness – such was the PC clone market born ..

    • SecretEuroPatentAgentMan

      Dragon and Tandy Color Computer both had more or less the same architecture and also used the 6809. As you say this was a nice CPU and quite shockingly also could multiply! The A and B accumulators could be concatenated into a double width D accumulator. Hitachi made the 6309 that added an E and F accumulator that likewise could be concatenated into the W wide accumulator that again could be concatenated with D into the quad width Q accumulator. The Japanese were rather systematic.

      The problem was that the software was dire and the BASIC was so slow you could type faster than the system could keep up with which even then was inexcusable. The BBC computer was felt to be faster than the 6809 computers which did not help Motorola.

      As for the schematics of the PC, I thought that was more or less the technical notes from Intel.

  5. I couldn’t agree more, Jamo, Noyce’s IC contributed much more to the future of microelectronics than Kilby’s but, in 1960, the US Patent Office can be excused for not knowing that.

  6. Well TI had to fight very hard for its patent on the IC, Jamo, I think Fairchild filed first and got the first issued patent on it. So it was as much a legal battle as a PR and marketing battle. And then there was Noyce’s perception that the planar process nade it practicable and Kilby’s perception that different functions could be made from the same material. It was a bit more than PR.

    • Kilby’s output from the Air Force funded Molecular Electronics program was I think more of a hybrid innovation than IC. Even RCA had more advanced outputs than TI. Fairchild, who decided not to take Air Force money were the ones who really invented ICs.

  7. Very many thanks for that Duncan, I didn’t know any of it. Most interesting – especially that Jobs tried to sell the Apple II to Commodore. History could have been very different!

    • Tech history is littered with Giants only because of the company Marketing and PR machine. TI and the invention of integrated circuits comes to mind. TI also tried hard on the invention of the microprocessor.

  8. Now that is very erudite, Jamo, I was thinking of the Apple II which first went on sale on June 10th 1977

  9. Interesting Fable this one David. Is it the Apple II with its 6502 processor or is it the TRS-80 with the Z80 processor. Or is it the Commodore PET with its 6502 processor ?

    You could argue the Trash 80 was more influential and the PET was the first with integrated monitor, keyboard and program loader mechanism.

    • By listing the “Trinity of 1977” you were bound to be right 🙂

      A complaint in the book “On The Edge” about the history of Commodore is about Apple and their fans claiming that they single handedly started the Microcomputer revolution. In contrast until the launch of VisiCalc Apple was in a distant third place.

      There are also a number of connections between the Apple II and Commodore.
      Commodore owned MOS who were the designers of the 6502,
      Steve Jobs tried to sell the Apple II design to Commodore who thought he wanted too much money so designed the Pet instead.

      Finally the 6502 was the “Lawsuit Compatible and pinout incompatible” version of the 6501 which was almost a copy of the Motorola 6800; not surprising as it was designed by the same people. The big selling point of the 6502 was the price which, due to better yields at MOS, was a fraction of any competing Microprocessor.

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