The first microprocessor, the TMX 1795, had the same architecture as the 8008 but was built months before the 8008. Never sold commercially, this Texas Instruments processor is now almost forgotten even though it had a huge impact on the computer industry. In this article, I present the surprising history of the TMX 1795 in detail, look at other early processors, and explain why the TMX 1795 should be considered the first microprocessor.
How did it have a huge impact on the industry if it was never released and didn’t have any descendants?
It’s in the article, the section that follows the sentence “The chip would have disappeared without a trace, except for one thing, which had a huge impact on the computer industry.”
I’m not convinced by the author’s claim.
The 8086 didn’t use the 8080 architecture and isn’t a development of the Datapoint 2200.
The 8086 was designed for high level languages (Pascal mostly) as is obvious in the instruction set, the 8008 and 8080 wasn’t.
But even calling the 8080 a descendant of the 8008 is an exaggeration.
You’re confusing 8080 and 8008…
Not really – the article states that the 8086 is derived from the 8080 and that in its turn is based on the 8008. But the chain breaks between the 8080 and the 8086.
The 8008 clearly evolved into the 8080 which evolved into the 8086. The 8080 has the same register set as the 8008 and includes the 8008’s instructions (encoded differently) as a subset.
The 8086 was designed to be assembly-language-level compatible with the 8080, so the 8080 register set and instruction set are subsets of the 8086 registers and instructions. It’s not strictly compatible, though, so some instruction conversion is required.
Reference: “Intel Microprocessors: 8008 to 8086”, Mazor et al.
It all boils down to the Intel 4004 vs TMX 1795… the article assumes based on *MARKETING* publications from the period that it was first. The 4004 was first to market thats all that matters really.
If they were first to silicon and it had flaws they never would have told anyone…
Our Wang 8008 sure didn’t like 8080 code.
But 808 state
Even ‘IBM compatibility mode’ wasn’t very reliable without fine tuning settings in each program, at least the programs that were certified compatible.
Studied electronics on TI ‘textbooks’. Great company, Thom.