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I just did the LC-3 one and look forward to learning a bit about dynamic recompilation using LC-3 as an (inappropriate) target machine in the current project.

I just did the LC-3 one and look forward to learning a bit about dynamic recompilation using LC-3 as an (inappropriate) target machine in the current project. Can you please elaborate why it is bad to use LC-3 for studying computer architecture? I do understand it is completely different from real hardware, and too simplified. But from the perspective of writing CPU emulators, is it bad for me?

saithound 2y ago
I answered a similar question by anyfoo downthread, the point about implementing a PIT should explain what I mean, and why I think that emulating a simple real architecture might be more useful while requiring similar effort.
- c0wb0yc0d3r 2y ago
  Link in case the order changes. https://news.ycombinator.com/item?id=42519788 https://news.ycombinator.com/item?id=42519788
- anyfoo 2y ago
  Again, you are coming at this from a software engineering direction, not a computer architecture/engineering one.
  - saithound 2y ago
    Since I have the exact same thought (that you are coming at this from a software engineering direction, not a computer architecture/engineering one), this is unlikely to be further productive :( You say you want students to be able to write emulators/simulators etc. (you list a bunch of software.engineering tasks). I say writing an LC-3 emulator won't give you any transferable skills for writing, say, a Gameboy Emulator (still a 30yo system), because these educational arhitectures are bad and abstract away precisely the things that you have to get right to do that, leaving you with something trivial to implement: a C array for "memory" and a few bitwise operations. Since we're largely looking at the same things and coming to orthogonal conclusions, I suggest we agree to disagree on this one.
    - liontwist 2y ago
      This article would directly apply to NES or game boy emulation. Yes, there are fewer instructions.
anyfoo 2y ago
When studying computer architecture, I think the implementation details of a real architecture, even a simple one, might actually slow you down if your goal is to learn about dynamic recompilation. The commenter you replied to seems to be coming from a software engineering perspective, i.e. learning how to program a computer (which someone interested in computer architecture probably knows about already).

saithound 2y ago

I answered a similar question by anyfoo downthread, the point about implementing a PIT should explain what I mean, and why I think that emulating a simple real architecture might be more useful while requiring similar effort.

c0wb0yc0d3r 2y ago
Link in case the order changes. https://news.ycombinator.com/item?id=42519788 https://news.ycombinator.com/item?id=42519788
anyfoo 2y ago
Again, you are coming at this from a software engineering direction, not a computer architecture/engineering one.
- saithound 2y ago
  Since I have the exact same thought (that you are coming at this from a software engineering direction, not a computer architecture/engineering one), this is unlikely to be further productive :( You say you want students to be able to write emulators/simulators etc. (you list a bunch of software.engineering tasks). I say writing an LC-3 emulator won't give you any transferable skills for writing, say, a Gameboy Emulator (still a 30yo system), because these educational arhitectures are bad and abstract away precisely the things that you have to get right to do that, leaving you with something trivial to implement: a C array for "memory" and a few bitwise operations. Since we're largely looking at the same things and coming to orthogonal conclusions, I suggest we agree to disagree on this one.
  - liontwist 2y ago
    This article would directly apply to NES or game boy emulation. Yes, there are fewer instructions.

anyfoo 2y ago

When studying computer architecture, I think the implementation details of a real architecture, even a simple one, might actually slow you down if your goal is to learn about dynamic recompilation. The commenter you replied to seems to be coming from a software engineering perspective, i.e. learning how to program a computer (which someone interested in computer architecture probably knows about already).