Most of the documents are available by getting lexide via rohms website, abd that comes bundled with a lot of docs, and you can also just Google a lot of it

Good correction, let me tighten what I meant so it stays precise:

• I agree Lapis/OKI/Rohm do publish extremely detailed manuals for their public MCUs/cores (ISA + bit-level behavior).
• The part that tends to be “reconstructed” in the Casio calculator context is typically the device-specific integration: SFR mapping for LCD/keys/backlight, memory map quirks, boot ROM behavior, and any board/SoC glue logic not necessarily the core ISA.

To keep this thread actionable (and not “google harder”), can you share one or two concrete identifiers?

• Exact doc names / PDFs shipped with Lexide Omega (e.g., “nX-U8 Instruction Manual”, “nX-U16 User’s Manual”)
• The MCU/part numbers they correspond to (e.g., ML62Qxxx / ML63Qxxx, etc.)
• Any public links or archive pointers (even if the IDE itself is painful)

If we can anchor the ISA to published manuals and separately list what’s still device-specific (SFRs + calculator hardware mapping), that answers OP’s question cleanly and avoids mixing “core architecture” with “Casio platform details.”

I can do that,
First the "NX-U16/100 Core Instruction Manual" can be found via Google or bundled with lexide, the chip itself which casio uses is proprietary meaning you will find nothing about it, but for classwiz X isn't is the ML620Q906 and for CW ML620Q909, to make stuff for it you need the dcl and trg files which contain all the sfr addresses and stuff. To get lexide you need to go onto rohms website and sign in/create an account, goto a random lsi, scroll down until you see development support or smth, and the lexide omega v2.1 should be there, it will say you need a license key, but you can bypass it by insect clementine the button and removing the requires key tag or something, it just let's you get it that easily.

What is officially documented

• The core ISA is documented in manuals such as:

  • “NX-U16/100 Core Instruction Manual” (and equivalent NX-U8 docs)

• These describe:

  • instruction formats
  • registers
  • execution behavior
    down to bit-level detail, as expected from Lapis/OKI/Rohm MCU documentation.

• These manuals are typically distributed with Lexide Omega and are tied to public MCU families (e.g. ML62Q series).

What is not publicly documented

• The Casio calculator SoC integration, including:

  • exact SFR mappings for LCD, keys, timers, backlight
  • boot ROM behavior
  • board-specific glue logic

• Those details live in DCL / TRG files and calculator-specific configs and are what emulator authors usually reconstruct.

Concrete chips used

• ClassWiz X: ML620Q906
• ClassWiz CW: ML620Q909

Practical takeaway

• If your goal is to understand or emulate the CPU core → published manuals + Lexide docs are sufficient.
• If your goal is to emulate or target Casio calculators specifically → reverse-engineering of SFRs and platform behavior is unavoidable.

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