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Comment by limikael | Hacker News Reader

So how many logic gates / transistors does it use in total? I tried to find this number in the article, but couldn't quite find it.

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I didn't do the math, but not many. Here's the 74XX ICs from the BOM list with short descriptions of what they are:

  74HC74  Dual D Flip-Flop
  74HC161 4-bit binary counter
  74HC541 Octal Buffer 
  74HC574 Octal 3−State Noninverting D Flip−Flop
  74HC14  Hex Schmitt−Trigger Inverter
  74HC08  Quad 2-input AND gate
  74HC02  Quad 2-input NAND gate
  74HC273 Octal D-type flip-flop with reset
  74HC138 3-to-8 line decoder/demultiplexer
  74HC139 Dual 2-to-4 line decoder

Though it's not straightforward to map microcode lookup through an EPROM into "gates".

Ignoring the memory, probably a similar number to the MyNOR[1] computer it's based off of, which has an all transistor implementation, the TraNOR[2], which has 2495 transistors.

[1] http://mynor.org/mynor.htm

[2] http://mynor.org/tranor.htm

Oh... Suddenly then it impresses me less because it sounds like quite a lot for something that calls itself "minimalistic". The 6052 processor has 3510 transistors, 2495 isn't that much lower.

"The complexity of my design is somewhere between the Intel i4004 CPU (2250 transistors) and the 6502 (3218 transistors). The i8080 already has 4500 transistors and the Zilog Z80 even has 8500 transistors, so you get an idea how small my design still is."

29% less transistors for similar capabilities would be good. How does the instruction set compare to 6502?

In terms of transistors I think MCPU by Tim Boscke can be hard to beat - https://github.com/cpldcpu/MCPU , however how many transistors this 8 bit CPU has is not clear.

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