A 4004 engineer (Stan Mazor) splits up the credit (Score 1)

Sometime back, I posted a note about the origins of the 4004 to comp.arch -- Stan Mazor, one of the engineers on the project replied with his take on how the credit should be split up.

This is his list, re-formatted in HTML:

1. Shima of Busicom specified ~8 custom chips, but there was some micro-coding for floating point operations using 16-digit primitive operations like shift left, add, subtract, etc.
2. Hoff believed there were too many complex special chips and that the micro engine was too high a level to be practical for Intel to design and build and proposed an alternative architecture.
3. Hoff proposed a simpler architecture using 4-bit data path and simple instructions based upon the PDP-8 model we were using at Intel to run 'Focal' programs.
4. Shima and Busicom opposed the Intel architecture at first. When I joined in Sept 1969 I was a computer designer for more than 3 years and just worked on Symbol at Fairchild, and did logic design on decimal floating point unit (like calculator).
5. Hoff and I did program 'snipets' to prove how we could code the '4004' to do calculator functions. I suggested enhancements to ISA including; JIN, FIN, and FIM, and some other minor stuff. The 4001- 4004 architecture was refined by Hoff and Mazor thru Dec. 1969, and by Jan 1970 Busicom agreed to our architecture.
6. The highlights of the architecture are explained elsewhere but include: on chip dynamic RAM for stack and registers, 4-bit data path, time multiplexing 16-pins, and I/O ports integrated on memory chips with local instruction decoding.
7. Faggin joined Intel after architecture was completed. Faggin did all logic design, circuit design, layout, production supervision, testing, etc. Faggin also 'invented' how to do capacitor with silicon gate which had very low gate/diffusion capacitance for bootstrapping amplifier for dynamic logic circuits.
8. Shima did all final calculator code, layout checking, logic checking and greatly contributed to the success of project; he also changed 2 instructions BBL and ADDC.
9. Intel filed patents on unique features of 4004, and the holders are Hoff, Faggin, Mazor.

In summary split the credit as follows;

• Noyce supported Hoff's proposal.
• Vasdasz was Hoff's boss and supported Hoff's choice.
• Shima/Busicom proposed using ROM coded routines.
• Hoff proposed simpler architecture and micro-coded vs special chips.
• Mazor helped refine ISA and chip architecture and wrote test code.
• Faggin did all chip design and took over 'ownership' of project.
• Numerous Intel employees helped in: mask layout, testing, packaging,etc.