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The 6809 was released in 1978, but looking at the usual source for price quotes for old computer components, Byte magazine, I cannot find any quotes for 1979. December 1980 lists it at $38, compared to its closest competitor, the Z80A, for $14.50.

Transistor counts for the Z80 and 6809 were 8500 and 9000 respectively, a very small difference. It sometimes happens that a new chip will be expensive for the first little while after release because the manufacturer is still debugging yield problems, but this was two full years later. Why was the 6809 still so much more expensive than the Z80?

  • Note that putting a lot of transistors into a chip is an accepted, but not the only and maybe not a very good measure for engineering effort that has gone into a CPU - Putting them in the right places is the art. The 6809 had a lot of them in the right places compared to other contemporary CPUs. – tofro Oct 19 '18 at 7:16
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    I have a speculation: the Z80 was much more widely used, there are many more of them, and so the manufacturing cost per chip is lower. – Wilson Oct 19 '18 at 7:43
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The price was defined obviously by marketing team, therefore their decisions are out of reach for the logical engineering mind :)

Probably they were relying on the marketing company (like this one https://cdn.hackaday.io/files/460001968064000/byte_6809_articlesx3.pdf) and thought people would be immediately convinced by cool features and buy 6809 whatever the price was, as there were no perceived alternatives in 8bit cpu market -- at that time.

Previously Motorola had to drop the price for 6800 after the release of 6502.

So I personally think people tend to recur -- and they were either to drop price if anything comparable would emerge or to keep it -- again. To my taste, however cool 6809 was -- it came a bit late, and the only thing that could make it a sound competitor was the appropriate price.

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    There were also other differences. The 6809 (like other moto chips of the time) used a two-phase clock and, new to the 6809, had a hardware multiply instruction (which was a new thing) - the Z80 used a single phase clock and had to implement multiplication as a macro. The clock differences gave the 6809 faster memory access and more efficient instructions at the cost of a longer full clock cycle time, which was useful in some applications. Overall the 6809 was a more modern design - the price also includes some of the costs of development. – J... Oct 19 '18 at 19:36
16

It was just standard market positioning. The 6800 was still a current product and in use in many systems at the time, so they priced the 6809 as a more powerful alternative to both that and the Z80.

The 6809 was expected to be used in higher end systems that cost more anyway, so Motorola naturally wanted their cut of that.

  • 15
    Absolutely. I bet an iPhone doesn't have 8 times more transistors than a $100 generic Android phone either. – Dmitry Grigoryev Oct 19 '18 at 13:27

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