{
  "added_at": "2026-11-10",
  "additional_evidence_urls": [
    "https://codeberg.org/gwetm/gyx-decomp/src/commit/c8a8e72fad3a1f127db5dc9ee1ed7e19aefdb4fe/build.bat",
    "https://codeberg.org/gwetm/gyx-decomp/src/commit/c8a8e72fad3a1f127db5dc9ee1ed7e19aefdb4fe/CONTRIBUTING.md",
    "https://codeberg.org/gwetm/gyx-decomp/src/commit/c8a8e72fad3a1f127db5dc9ee1ed7e19aefdb4fe/src/features/features.inc",
    "https://codeberg.org/gwetm/gyx-decomp/src/commit/c8a8e72fad3a1f127db5dc9ee1ed7e19aefdb4fe/src/main.c"
  ],
  "category": "reconstruction-cases",
  "class": "hardware",
  "description_en": "gyx-decomp is a decompilation of the Casio ES PLUS GYX scientific calculator firmware, which runs on ROHM nX-U8/100 microcontrollers. Code Casio wrote in C is recovered as ANSI C that the CCU8 compiler turns into matching assembly, Casio assembly is disassembled and reworked for RASU8, and MCU startup code is recreated from files for other U8 parts. A build script compiles, links with RLU8, converts to Intel HEX and binary, and a features file switches modes and functions to build custom ROMs. Notes cover the memory model, compiler options, segment naming and link order.",
  "description_zh": "gyx-decomp 是 Casio ES PLUS GYX 科学计算器固件的反编译项目，该固件运行在 ROHM nX-U8/100 微控制器上。Casio 用 C 编写的部分被还原为 ANSI C，经 CCU8 编译可得到匹配的汇编；Casio 手写的汇编被反汇编并改造为可用 RASU8 汇编；MCU 启动代码则参照其他 U8 芯片的文件重建。构建脚本依次编译、用 RLU8 链接并转换为 Intel HEX 和二进制，功能配置文件可开关各模式和函数以生成定制 ROM。附带的说明记录了内存模型、编译选项、段命名和链接顺序方面的发现。",
  "entry_url": "https://awesomerea.org/resources/gyx-decomp-case/",
  "entry_url_zh": "https://awesomerea.org/zh/resources/gyx-decomp-case/",
  "evidence_url": "https://codeberg.org/gwetm/gyx-decomp/src/commit/c8a8e72fad3a1f127db5dc9ee1ed7e19aefdb4fe/README.md",
  "group": "cases",
  "id": "gyx-decomp-case",
  "json_url": "https://awesomerea.org/resources/gyx-decomp-case/record.json",
  "kind": "case-study",
  "markdown_url": "https://awesomerea.org/resources/gyx-decomp-case/index.md",
  "markdown_url_zh": "https://awesomerea.org/zh/resources/gyx-decomp-case/index.md",
  "name": "gyx-decomp: Casio ES PLUS GYX firmware decompilation",
  "name_zh": "gyx-decomp：Casio ES PLUS GYX 计算器固件反编译",
  "record_type": "resource",
  "relationship": "independent-reconstruction",
  "requirement_facets": [
    "prerequisites",
    "limits",
    "limits",
    "license"
  ],
  "requirements": [
    "Building needs Windows with the LAPIS U8/U16 Development Tools (CCU8 and the MACU8 Assembler Package), the bundled ML610904.DCL device file, and Python with the intelhex library for binary conversion.",
    "The diagnostic test-select menu of GY454X VerF and GY455X VerF and the extra conversions of Japanese models are missing, and not all feature toggles are implemented.",
    "Assembly comments, readable C and the RLU8 link order are still being worked on.",
    "No licence file in the repository."
  ],
  "requirements_zh": [
    "构建需要 Windows 及 LAPIS U8/U16 开发工具（CCU8 与 MACU8 汇编器套件）、仓库自带的 ML610904.DCL 器件文件，转换为二进制还需 Python 和 intelhex 库。",
    "尚缺 GY454X VerF 与 GY455X VerF 的诊断测试选择菜单以及日本型号的额外换算功能，部分功能开关也未实现。",
    "汇编注释、C 代码可读性和 RLU8 链接顺序仍在完善中。",
    "仓库中没有许可证文件。"
  ],
  "targets": [
    "firmware"
  ],
  "url": "https://codeberg.org/gwetm/gyx-decomp",
  "verification": "source-reviewed",
  "verified_at": "2026-11-09"
}