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According to Wikipedia, The Motorola 6800 was released in 1974. Between that and the release of the 6809 in 1979 (or 1978?) there was at least one other 6800-series CPU released, the 6802 microcontroller with the same registers and instruction set as the 6800. The 6801/6803 microcontrollers, which added some additional instructions, were apparently released in 1978 or 1979, but I don't know if this was before or after the 6809.

I'd like a list of all 6800-like processors and microcontrollers released by Motorola up to the time the 6809 became available for purchase in non-sample quantities, along with notes on programming model changes (such as additional instructions or registers). I don't need details about changes, on-chip or not, that are not directly part of the CPU, such as on-board memory or I/O.

I'm mainly interested in availability dates, by which I mean the date any random person or company could walk in off the street and buy them in quantities of a thousand or more. But feel free to provide announcement dates, too, so long as the announcement covers the final details of the processor programming model.

  • 1
    These definitions are rather unclear, as 'Release Dates' are usually a marketing tool. Availability can be before and after (usually after), also the 'I' in "when could I actually buy one" covers quite a range, as new devices are usually offered at different times first to different channels. – Raffzahn Jul 30 at 7:25
  • Good point. I've tried to clarify this in the question; let me know if it's more clear now. – Curt J. Sampson Jul 30 at 7:37
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Figure 1-1 (page 1-4) in [mot81] gives an overview of the early days of the 6800 family:

Genealogy of the cohesive M6800 microprocessor/microcomputer family

This can't be read for exact dates so I've included everything that is not clearly after the 6809 and added further details from other sources documented below.

Production  Annnounced      Product
1974-11     1974-03         6800 microprocessor
1976-07?    ?               68A00, 68B00 (1.5 and 2 MHz)
            1977-03         6802, 6808 (onboard clock+RAM, clock)
            1978-08         6801, 6803
1979?       1978-07?        6809, 68HC09
            1979?           6805
            1979-12         68HC05
  • 6800: "[A]nnounced in March 1974 and was in full production by the end of that year." "The M6800 microcomputer system was finally in production by November 1974." Sourced in [wp6800].

  • 68A00, 68B00: "The new parts were available in July 1976." Sourced in [wp6800].

  • 6802, 6808: Added onboard clock and (6802 only) 128 bytes of RAM. Announced by March 3rd 1977. Sourced in [wp6800].

  • 6801, 6803: Adds 16-bit "D" register as concatenation of A and B and various new instructions, including multiply. Slightly to the left of 1979 in the [mot81] diagram, though data sheets for it don't appear until [mot83mpu]. [wp6800] references "Product Preview MC6801, Austin, Texas: Motorola Semiconductor Products. August 1978. NP-93." This or a very similar MCU appears to have been in use by General Motors as early as 1977[shack]; it's referred to in [oral] as a "GMCM" and in [mot88v1] Figure 1-1 (p. 1-3) as "custom CPU."

  • 6809: The earliest mention I can find that includes a month is in an Elsevier journal.[[elsev]] This seems unlikely to be the initial announcement, but is probably well before production. (6809s were not on sale in the back pages of Byte in December 1977.)

  • 6805: Optimized for controller applications; incompatible architectural changes such as X register reduced to 8 bits. It may have existed internally at Motorla as early as 1977 or 1978: "this is '77-'78 timeframe -- they came and said, 'Hey, we'd like to have a CMOS version of this 6805 variant."[oral]. (The M14605 is the CMOS 6805. It and several 6805 variants have data sheets in [mot81].) [shack] claims release in 1979. archive.org has an M6805 M14605 Family Users Manual dated 1980.

  • 68HC05: "A low-power variation of the 05," "shipped..in December of 1979."[oral]

In case you're wondering about the "holes" in this numbering scheme: The 6804 was a reduced cost modification of the 6805 released around 1982. The 6806 and 6807 designations were never used, as far as I can tell. The 6810 was a RAM chip. The 6811 was a 6801 extension introduced in 1984. The 6812 in turn extended that, but not until the 1990s. From the beginning parts from 6820 onwards were peripherals.

References

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