Friday, September 7, 2007

Intel 4004 isn't the world's first microprocessor

Recently while I was giving an introductory lecture on microprocessor to Computer Engineering students, someone asked me about the evolution/history of microprocessors. I'm really not very good at remembering dates, but then I started speaking about it. After sometime, when I reached the year 1992, and the Intel Pentium processor at 66Mhz, a boy stood up and asked me which was the first microprocessor. I showed him the board where I had written the CADC (MP944), and he showed me the book which showed Intel 4004. I said, "I'm pretty sure it is MP944, and I've been teaching that to a few students", but I'm bad with dates, so thought I should check.

Looking at all the textbooks and reference books suggested by the University syllabus, I realized that all books were claiming the Intel 4004 to be the first microprocessor. I was a little shocked, coz I remembered reading a paper here, and discussions with my senior professors and colleagues, that the MOS-LSI based MP944 was the first microprocessor. I did some analysis with my students, who had never heard of that chip and drew on the board what I remembered... (Here's a better one from Ray Holt, the chip architect himself).



Looking at the diagram, the student argued that it was a 4-chip design, and I showed him that 4004 was also a part of a 4-chip chipset. The date for the chip's papers were older as old as 1968, which made everyone sure that the books had wrongly called the Intel 4004, the first microprocessor. We later found this from IBM which agreed to my observations.

I hope most textbooks and authors should acknowledge Ray Holt's designs from AI Garrett and give the facts correctly.

1 comment:

Anonymous said...

Saptarshi,
Thank you for doing the research on the F-14 microprocessor chip set. I have made a new site and will reference your site.

Ray Holt