{"id":44029300,"url":"https://github.com/ioncodes/gg","last_synced_at":"2026-02-07T18:37:31.473Z","repository":{"id":225209038,"uuid":"729136670","full_name":"ioncodes/gg","owner":"ioncodes","description":"GameGear emulator with partial Sega Master System support","archived":false,"fork":false,"pushed_at":"2024-03-02T01:24:30.000Z","size":103149,"stargazers_count":13,"open_issues_count":2,"forks_count":2,"subscribers_count":1,"default_branch":"master","last_synced_at":"2025-12-13T09:55:01.302Z","etag":null,"topics":["emulator","gamegear","sega","sega-master-system"],"latest_commit_sha":null,"homepage":"","language":"Rust","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/ioncodes.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null}},"created_at":"2023-12-08T13:57:02.000Z","updated_at":"2025-11-17T22:07:40.000Z","dependencies_parsed_at":"2024-02-29T20:38:40.099Z","dependency_job_id":null,"html_url":"https://github.com/ioncodes/gg","commit_stats":null,"previous_names":["ioncodes/gg"],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/ioncodes/gg","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/ioncodes%2Fgg","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/ioncodes%2Fgg/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/ioncodes%2Fgg/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/ioncodes%2Fgg/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/ioncodes","download_url":"https://codeload.github.com/ioncodes/gg/tar.gz/refs/heads/master","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/ioncodes%2Fgg/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":29203785,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-02-07T17:44:10.191Z","status":"ssl_error","status_checked_at":"2026-02-07T17:44:07.936Z","response_time":63,"last_error":"SSL_connect returned=1 errno=0 peeraddr=140.82.121.6:443 state=error: unexpected eof while reading","robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":false,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["emulator","gamegear","sega","sega-master-system"],"created_at":"2026-02-07T18:37:26.287Z","updated_at":"2026-02-07T18:37:31.464Z","avatar_url":"https://github.com/ioncodes.png","language":"Rust","funding_links":[],"categories":[],"sub_categories":[],"readme":"## gg\nWIP GameGear (and possibly Sega Master System) emulator. Most of the information I either figured out by reverse engineering\nthe hardware and software myself or by using the excellent docs found on [smspower.org](https://www.smspower.org/). This project is \nmessed up in some cases and should not be used as direct reference for your own implementation. I mostly implemented everything on a\n\"fuck around and find out\" basis, implementing features where needed to get things working. Also, there is no PSG support! Oh, and I\nused AI to generate the z80 opcode parser / jump table. :)\n\n\u003cdetails\u003e\n  \u003csummary\u003eDemos\u003c/summary\u003e\n\n  | Sonic The Hedgehog 2 Demo                                                                         | Lucky Dime Caper Starring Donald Duck Demo                                                        | Pac-Man Demo                                                                                      | Earthworm Jim Demo                                                                                |\n  | ------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |\n  | \u003cvideo src=\"https://github.com/ioncodes/gg/assets/18533297/afd20259-47d0-4dd6-86b8-abe68bc0a4e6\"\u003e | \u003cvideo src=\"https://github.com/ioncodes/gg/assets/18533297/9ac07dca-3b54-43b2-a881-163980319dff\"\u003e | \u003cvideo src=\"https://github.com/ioncodes/gg/assets/18533297/1549887c-45f5-4eec-9201-9e4de168b32e\"\u003e | \u003cvideo src=\"https://github.com/ioncodes/gg/assets/18533297/3812319b-5b0e-4841-99c7-e3f084279b67\"\u003e |\n\u003c/details\u003e\n\nI would not have gotten this far without the amazing help from the helpful people over on the [Emulation Development](https://discord.gg/dkmJAes) Discord server:\n* originaldave_\n* ZjoyKiLer\n* Mask of Destiny\n* and everyone else that helped along the way \u003c3\n\nMandatory quote:  \n\u003e Layle - certified idiot — Yesterday at 9:49 PM  \n\u003e i am  \n\u003e officially an idiot\n\n## Compatibility List\n| **Title**                                                                     | **CRC32**  | **Status** |\n| ----------------------------------------------------------------------------- | :--------: | :--------: |\n| [BIOS] Sega Game Gear (USA) (Majesco)                                         | `0ebea9d4` |     👌      |\n| Pac-Man (USA)                                                                 | `b318dd37` |     👌      |\n| Sonic The Hedgehog 2 (U) [!]                                                  | `95a18ec7` |     👌      |\n| Sonic \u0026 Tails (Japan) (En)                                                    | `8ac0dade` |     👌      |\n| Sonic \u0026 Tails 2 (Japan)                                                       | `496bce64` |     👌      |\n| Sonic Labyrinth (World)                                                       | `5550173b` |     👌      |\n| Sonic The Hedgehog - Triple Trouble (USA, Europe, Brazil) (Beta) (1994-08-08) | `80eb7cfb` |     👌      |\n| Lucky Dime Caper Starring Donald Duck, The (USA, Europe)                      | `07a7815a` |     👌      |\n| Sonic The Hedgehog (U) (V1.0) [!]                                             | `3e31cb8c` |     👌      |\n| Earthworm Jim (Europe)                                                        | `691ae339` |     🐥      |\n| Batman Returns (World)                                                        | `7ac4a3ca` |     🐥      |\n| Ecco the Dolphin (Japan)                                                      | `a32eb9d5` |     🐥      |\n| Ecco - The Tides of Time (USA, Europe, Brazil)                                | `e2f3b203` |     🐥      |\n| GG Shinobi II, The ~ Shinobi II - The Silent Fury (World)                     | `6201c694` |     🐥      |\n| Asterix and the Great Rescue (Europe) (En,Fr,De,Es,It)                        | `328c5cc8` |     🐣      |\n| Tom and Jerry - The Movie (USA, Europe)                                       | `5cd33ff2` |     🐞      |\n| Shinobi (USA, Europe)                                                         | `30f1c984` |     🐞      |\n\n* 👌: No known issues\n* 🐥: Playable with a few bugs\n* 🐣: In-Game, but only limited playability\n* 🐞: Bugged/Broken\n\nNote: This rating is completely subjective.\n\n## Running\nIt is strongly recommended to run the emulator in release mode, no matter what.\n```\ncargo run --release -- --bios bios.gg --rom game.gg\n```\n\nIt is possible to dump debug and/or trace information either to stderr or a file:\n\n```\nUsage: gg.exe [OPTIONS] --bios \u003cBIOS\u003e --rom \u003cROM\u003e\n\nOptions:\n  -b, --bios \u003cBIOS\u003e\n  -r, --rom \u003cROM\u003e\n  -l, --lua \u003cLUA\u003e\n  -c, --cpu-test\n  -l, --log-level \u003cLOG_LEVEL\u003e  [default: info]\n  -l, --log-to-file\n  -h, --help                   Print help\n```\n\n## Debugging\nThe emulator features a debugger built around [egui and eframe](https://github.com/emilk/egui). It is very simple and hosts the following features:\n\n* Memory Viewer (ROM, RAM, SRAM, VRAM, CRAM)\n* Display CPU memory address mappings (ROM / RAM banks)\n* \"Resume\", \"Break On\" and \"Step\" debugger controls\n* Disassembly \u0026 Trace\n* View CPU and VDP infromation such as registers\n* SDSC Debug Console\n\nThere's more features that are CLI only:\n* Lua scripting (pretick/posttick hooks with access to CPU \u0026 VDP state and memory)\n* Debug and trace logging (\"debug\", \"trace\")\n\n## Testing\nCurrently the Z80 implementation can be tested using [ZEXDOC/ZEXALL](https://github.com/maxim-zhao/zexall-smsjsm) and using the JSON unit tests \nprovided by [jsmoo](https://github.com/raddad772/jsmoo/tree/main/misc/tests/GeneratedTests/z80/v1). However, some features are ignored/disabled/not implemented.\n\n### ZEXDOC \u0026 ZEXALL\n`zexdoc` is built into the emulator and can be executed by passing the `--cpu-test` flag.\n\n### JSON Tests\n`cargo test` in the workspace folder will launch all unit tests. The current implementation measures only registers and RAM content. Status at the time of writing:  \n```\ntest result: FAILED. 1388 passed; 222 failed; 0 ignored; 0 measured; 0 filtered out; finished in 66.36s\n```\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fioncodes%2Fgg","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fioncodes%2Fgg","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fioncodes%2Fgg/lists"}