Hitachi HD6801S0PJ – 1982 Automotive Spec 6801

The original Motorola MC6801 was released in 1977, built on a 5.1u NMOS process with 35,000 transistors (some sources say 25,000, which may be the ‘active’ transistor sites).  One of the very first customers was General Motors, you can read more about that in last years article on the 6801.  Hitachi was the primary second source for Motorola, primarily to supply the Japanese market, but they also competed with Motorola in the US market as well.  Hitachi released their version of the 6801 in 1980, with full production commencing in 1981.  It was made on a 3-micron NMOS process and was available in both a 1MHz speed (HD6801S0) and 1.25MHz (HD6801S5).  Around this time (1982) Hitachi was also transitioning their part numbering system.  Originally these parts were HD468xx… which was a bit confusing so they dropped the ‘4’.  For several years in the early 1980’s it is not uncommon to find parts with either, or both part numbers on them.

The pictured Hitachi HD6801S0P in interesting for a couple reasons.  The A00 denoted the ROM code for the 2K of onboard ROM.  A00 means that it is unprogrammed.  This would be useful for testing the 6801 with an external EPROM etc.  The ‘J’ on the package denotes that this device is a industrial/automotive spec part with an increased temperature range, in this case -40-85C.  Hitachi date codes are different from other manufacturers but are relatively simple.  The code 2E1 denotes the first week (1) of May (E) in 1982 (2).

Hitachi marked with both old and new part numbers
HD46800DP and HD6800P – dated 3F1 – First week of June 1983

*Years repeat, so 0 is used from 1980 and 1990
** ‘I’ is skipped to avoid confusion with the number ‘1’

What is perhaps more interesting is what came with this CPU when the museum got it.  Its often hard to figure out what a CPU/MCU was used in, or what it was for, its provenance.  This 6801 offers some help.  It came in an original Hitachi box, with a copy of a fax from Hitachi in Japan to the Hitachi sales office in the USA.  The fax denotes that these are qualification samples, automotive spec, and for a particular customer.  That customer is Chrysler (the automotive company now owned by Fiat).

Fax from Hitachi Japan stating use of the HD6801 samples

Also included on the fax is an original Japanese date stamp (June 1982 (Showa year 57)) .  These 6801s were fresh off the production line, having been made only a few weeks earlier.   The fax states these are for Chrysler in Huntsville, AL. with a reminder that they are “Not for Detroit” (where most of Chrysler production was.  That is an interesting addition, and important, as Chrysler did (it closed in 2011) have a very large presence in Huntsville, AL.  Huntsville is known as Rocket City, home of the Redstone Arsenal, where a large amount of US rocket, missile, and space engineering have taken place.  It was also the home of Chrysler Electronics (as well as most all of Chrysler’s military and space programs.  It was Chrysler who built the Saturn 1 and Saturn 1B upper stages for the NASA Apollo program.  Chrysler Electronics also built much of the Grown system electronics for the Apollo program as well as vehicle testing equipment for the M1 tank, the M2/3 Bradley and a host of other military programs.

Chrysler SERV – Space Shuttle Concept

Chrysler also proposed the Single-stage Earth-orbital Reusable Vehicle (SERV) during the design phase of what became the Shuttle program.

In the early 1970’s electronic use in cars was growing rapidly, leading Chrysler to greatly expand their presence in Huntsville.  These 6801s were likely for testing for cars, though it is unclear if Chrysler actually used the 6801 in their vehicles as ECUs from the mid-80’s all seem to be running the 6803 and 6805 MCUs.  Maybe if I find an early 80’s Chrysler I’ll tear out the ECU and find out.

SESCOSEM SFF96800K – Dated 7651 and made by Motorola

Sescosem was a French company that was formed during the merger of Thomson-Brandt and CSF in 1968.  Thomson-Brandt has its roots as a French subsidiary of GE back in 1892 as Compagnie Française Thomson-Houston (CFTH), while CSF was a French electronics company founded in 1918.  Thomson’s SESCO division (itself a joint venture between Thomson and General Electric) was merged with CSF’s COSEM division to form SESCOSEM.  SESCOSEM made many semiconductor products for the European market, starting with basic transistors and eventually second-sourcing microprocessors.

Sescosem SFF71708K – Mid 1978 – 2708 EPROM – Note the SESCOSEM logo

SESCOSEM began to work as a second-source for Motorola in September 1976.  Somewhat unusually SESCOSEM did not originally manufacture the IC’s they sold.  They received completed devices from Motorola, and remarked them as their own.  This may sound odd, but it served a purpose, it increased SESCOSEM’s market, and allowed Motorola to more easily sell their devices in Europe.  Buying local, to support the domestic industry, was, and continues to be important in Europe, so buying ‘Motorola’ devices, made in the US was less appealing then buying a ‘local’ chip, despite that chip simply being remarked. The agreement called for Motorola to supply
masks and information concerning the 6800 to Thomson-CSF (SESCOSEM parent) for present and future microprocessor products.  Eventually SESCOSEM was able to begin making their own devices at their 2 production facilities: Saint-Égrève , near Grenoble (COSEM site) and Aix-en-Provence (SESCO site).

Sescosem SFF71708J – Another 2708 but made in late 1979, note the switch to the Thomson Semiconductor logo

SESCOSEM also made/sold the various support products for the 6800 series, as well as several EPROM’s, including a clone of the 1702, 2708 and 2716. In mid-1979 SESCOSEM stopped using their own logo, and switched to that of Thomson and in 1982 SESCOSEM was rolled into Thomson Semiconductor, as the French government nationalized and consolidated many industries in an attempt to increase profitability.  Thomson Semiconductor also included Mostek (sold to Thomson in 1985), Silec,  Eurotechnique (French-National Semi joint venture) and EFCIS.  This allowed Thomson to produce Motorola designs, now including the 68000 series of processors. In 1987 SGS of Italy, merged with Thomson to form SGS-Thomson, what is now known today as STMicroelectronics.

While a bit convoluted, this is one reason so many companies manufactured Motorola products.  This helped contribute to the world-wide success of Motorola products.  No longer were they only a US product, but a global product, made and sold by global companies.  In a twist of irony, Freescale, the semiconductor portion of Motorola, was purchased by NXP Semiconductors of the Netherlands in 2015, adding yet another brand of 6800 and 68000 processors.  Only a year later however, in October of 2016 Qualcomm, one of the leading makers of cell-phone chipsets, announced that it will be purchasing NXP.  A Qualcomm 68k processor may very well be in our future.

Motorola 6800/BQCJC – Mil-spec 6800 from 1985

The Motorola MC6800 was Motorola’s first full 8-bit processor.  Introduced in 1974 it was a very good processor, and at the time it did not have a lot of competition, mainly the Intel 8080 and 8008.  Within 2 years though it was competing against the 6502. the 1802, the Z80 and a host of other processors.

This particular example was made in 1985 and is a MIL-STD-883 rated device for use in high reliability military applications.

But the 1980s 8-bit designs were surpassed by 16 and 32-bit designs for most computer use, leaving the 8-bit MC6800 to largely be relegated to use in embedded application and microcontroller work.   Motorola made several version of the 6800 specifically for use as MCUs, the 6802, the widely used 6805 (and its CMOS version the 68HC05) and the 68HC08.  All of which are still in use today, 40 years after Motorola made the first 6800.  The 6800 (and its derivatives also continue to be used as IP cores, read for dropping into ASIC/FPGA designs.  Just this year Digital Core Designs added the 68HC08 to their library of available IP cores.

MOS MCS6501 – November 1975

One of the classic stories of the 1970’s microprocessor boom times was that of MOS Technologies at WESCON (Western Electronics Show and Convention) on September 16th 1975 in San Francisco.  MOS Technology was a newcomer to microprocessors.  They had with them two brand new processor design, the MCS6501 and the MCS6502 which they hoped to sell on the floor at Wescon, for $20 and $25 each.  However Wescon forbid sales on the convention floor, so quick thinking by MOS Technologies Chuck Peddle directed people to a hotel room, where “the beer was free and chips were $25.”  In the room were jars of 6501 and 6502 processors, to give them impression that these were in full production.  In reality the bottoms of the jars were filled with defective parts.  It was no matter, the 6500 series was a huge hit, led largely by its availability, low price and marketing to everyone (not just ‘big corporate users’).  The 6500, and specifically the 6501 have an interesting story leading up to that fateful day at WESCON.

Motorola XC6800B – July 1975 – Pre-production part, not something MOS bothered with.

It begins at Motorola, where Chuck Peddle, Bill Mensch and several others were employed in the early 1970’s design the MC6800 processor and its peripherals.  The 6800 was not a bad design, it was however, very expensive, a development board for it costing over $300.  Chuck worked largely as the 6800 system architect, ensuring all the ICs worked well together and were what was needed to meet customers needs.  He attended many calls to potential clients and noted that many were turned off by one thing, price.  With that in mind he sought out to build a lower cost version of the 6800 using some of the newer processes available (specifically depletion mode NMOS vs the enhancement mode of the 6800).  Motorola management wouldn’t hear it, they wanted nothing to do with a lower cost processor available to the masses.  And with that, Chuck, Bill and over half the 6800 team left.

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8-bit 8MHz w/ ADC and 16K EPROM

One of the most well known microcontroller families is the Intel MCS-51.  It was introduced in 1980 and is still being made in many many forms.  It, however, is not the only popular 8-bit microcontroller.  Motorola made many microcontroller versions of the famous 6800 CPU.  Namely the MC6804 and the still in production 68HC05 series.

ST, which was formed by the merger of SGS of Italy, and Thomson of France, also makes a wide range of 8-bit microcontrollers which are very popular and widely used.  The ST7 microcontroller is a 8-bit Von Neumann architecture (shared address/data bus) MCU.  It is a serial accumulator design (so all operations occur in the accumulator, rather than in a wide set of registers like the 8051).  The ST7 was introduced in the early 1990’s as an upgrade to the ST6 Family of microcontrollers.  The ST7 added more high level programming support, and better interrupt handling.  The ST7 provides higher performance then many competing architectures and in various performance tests such as IRQ handling, returns, instruction execution times etc, it even beats the venerable 80C51.

Both the ST6 and ST7 families are based on the Motorola MS680x microcontroller family.  The ST6 closely resembles the 6804 and the ST7 is upwards code compatible with the MC68HC05 (assembly level translators exist to port the raw code).  The ST7 has 63 instructions and the 6805 has 62 (depending on version).  It is not an uncommon practice for one MCU to be based off, or even compatible with another.  It provides more familiarity for programmers and design engineers.  What really sets a MCU apart is the peripherals that surround the core, and its operating parameters.  The ST6 and ST7 are both highly respected for their ESD protection and high noise immunity.  These features were both carried over into the ST8M family that was introduced in 2008 to replace the aging ST7.  The ST7 can be found in many applications such as automotive  appliance control, motor control, and other embedded systems that most people forget are run by a processor.