WQXEmu - RetroBIOS¶
Technical notes
Wenquxing electronic dictionary emulator written in Rust by AloysHF. The libretro core and the wqx-emu standalone binary share the wqxemu-core crate, which runs the original firmware of five models on an emulated 6502 SoC: NC1020, PC1000, CC800, NC2000 and NC3000. The git.libretro.com repository is a mirror of the GitHub one at the same commit; the buildbot consumes its .gitlab-ci.yml.
The core takes no content. retro_load_game refuses a non-null game info (crates/wqxemu-libretro/src/lib.rs:632-635) and the machine is started through Start Core, supports_no_game being set (crates/wqxemu-libretro/src/lib.rs:476-481). The model comes from the wqxemu_model core option, NC1020 when unset (crates/wqxemu-libretro/src/lib.rs:263-282, crates/wqxemu-libretro/src/lib.rs:956-973), and its firmware set is built as {system}/WQXEmu/<model>/<file> (crates/wqxemu-libretro/src/lib.rs:211-248, model names in crates/wqxemu-core/src/machine.rs:35-43). Every path of the set must be a regular file, otherwise retro_load_game names the missing paths and returns false (crates/wqxemu-libretro/src/lib.rs:250-257, crates/wqxemu-libretro/src/lib.rs:644-658). Only the set of the selected model is read.
Each machine reads its files whole with std::fs::read and checks their size only: a ROM or NOR image must be at least as large as the window it fills, the PC1000 ROM must be exactly 12 MiB or 16 MiB, and NAND images are copied without any check. A file that fails the check makes Emulator::new fail and retro_load_game returns false with the loader's message (crates/wqxemu-libretro/src/lib.rs:671-677). No hash is verified.
The firmware files are never written. Neither frontend calls save_nor; the writable flash, NAND, RAM and peripheral state of a session is serialized to {save}/<model>/<fingerprint>.wqxs, a gzip file the core creates on unload and reloads at the next start of the same model and firmware set (crates/wqxemu-libretro/src/lib.rs:316-340, crates/wqxemu-libretro/src/lib.rs:679-693, crates/wqxemu-core/src/save.rs:43-88). The fingerprint is an FNV-1a over the slot layout and the content of every file of the set (crates/wqxemu-core/src/machine.rs:89-113). That file is created by the core. retro_get_memory_data returns null for every memory id (crates/wqxemu-libretro/src/lib.rs:875-885).
The standalone binary takes the same files as explicit --rom, --nor, --nand and --nand0 paths and has no default directory; --model selects the machine, otherwise detect_model guesses it from the file sizes (crates/wqxemu/src/main.rs:27-42, crates/wqxemu/src/main.rs:243-278, crates/wqxemu/src/main.rs:280-292, crates/wqxemu-core/src/machines/mod.rs:38-87). Its device skins are include_bytes! PNGs, or drawn by code_skin when --skin code is given (crates/wqxemu/src/main.rs:65-67, crates/wqxemu/src/keypad.rs:86-91, crates/wqxemu/src/keypad.rs:220-227).
The libretro-core-info file names the PC1000 NOR image pc1000.fls. The code opens pc1000.nor since commit 0a8f7a5 of 2026-08-23; the v0.1.0 tag predates that commit and opens pc1000.fls.
12 files | 11 required, 1 optional | 12 in repo, 0 missing
obj_lu.bin required in repo
NC1020 system ROM, three 8 MiB volumes
- Path:
WQXEmu/nc1020/obj_lu.bin - System: wenquxing-nc1020
- Size: min 24.0 MB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:214-219,crates/wqxemu-core/src/machines/nc1020.rs:61-98,crates/wqxemu-core/src/memory.rs:24 - Read whole from {system}/WQXEmu/nc1020/obj_lu.bin. The image must be at least 0x8000 * 0x300 bytes or the loader fails; a larger file is kept whole. Each 32 KiB bank is stored with its 16 KiB halves swapped and is swapped back on load, and the BBS pages are mapped from it.
nc1020.fls required in repo
NC1020 NOR flash, 32 banks of 32 KiB
- Path:
WQXEmu/nc1020/nc1020.fls - System: wenquxing-nc1020
- Size: min 1.0 MB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:214-219,crates/wqxemu-core/src/machines/nc1020.rs:101-122,crates/wqxemu-core/src/memory.rs:26 - Read whole from {system}/WQXEmu/nc1020/nc1020.fls. The image must be at least 0x8000 * 0x20 bytes or the loader fails; only the first 1 MiB is used, with the same 16 KiB half swap as the ROM. Writes go to the in-memory copy and are persisted in the .wqxs session file, never to this file.
pc1000.rom required in repo
PC1000 system ROM, obj1 + obj2 + obj3
- Path:
WQXEmu/pc1000/pc1000.rom - System: wenquxing-pc1000
- Size: 12.0 MB / 16.0 MB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:220-225,crates/wqxemu-core/src/machines/pc1000.rs:38-40,crates/wqxemu-core/src/machines/pc1000.rs:236-283 - Read whole from {system}/WQXEmu/pc1000/pc1000.rom and stored linearly. Exactly 12 MiB (obj1, obj2, obj3 back to back) or 16 MiB (the PC1000EMUX and Android layout, obj3 at 12 MiB with 8 to 12 MiB unused) is accepted; any other size fails the loader. The volume tables are rebuilt for the layout found.
pc1000.nor required in repo
PC1000 NOR flash, 16 banks of 32 KiB
- Path:
WQXEmu/pc1000/pc1000.nor - System: wenquxing-pc1000
- Size: min 512.0 KB
- Aliases:
pc1000.fls - Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:220-225,crates/wqxemu-core/src/machines/pc1000.rs:42,crates/wqxemu-core/src/machines/pc1000.rs:284-313 - Read whole from {system}/WQXEmu/pc1000/pc1000.nor. The image must be at least 0x80000 bytes or the loader fails; only the first 512 KiB is used. A dump stored with swapped 16 KiB halves is recognised by the info-block signature at bank 0 offset 0x4000 and unswapped. The v0.1.0 tag and the libretro-core-info file name it pc1000.fls.
obj.bin required in repo
CC800 system ROM, two volumes of 256 banks
- Path:
WQXEmu/cc800/obj.bin - System: wenquxing-cc800
- Size: min 16.0 MB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:226-231,crates/wqxemu-core/src/machines/cc800.rs:38,crates/wqxemu-core/src/machines/cc800.rs:229-251 - Read whole from {system}/WQXEmu/cc800/obj.bin. The image must be at least 0x1000000 bytes or the loader fails; only the first 16 MiB is used. Each 32 KiB bank is stored with its 16 KiB halves swapped and is swapped back on load. Volume 0 is banks 0 to 255, volume 1 banks 256 to 511.
cc800.fls required in repo
CC800 NOR flash, 16 banks of 32 KiB
- Path:
WQXEmu/cc800/cc800.fls - System: wenquxing-cc800
- Size: min 512.0 KB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:226-231,crates/wqxemu-core/src/machines/cc800.rs:40,crates/wqxemu-core/src/machines/cc800.rs:252-267 - Read whole from {system}/WQXEmu/cc800/cc800.fls. The image must be at least 0x80000 bytes or the loader fails; only the first 512 KiB is used, with the same 16 KiB half swap as the ROM.
nc2000.nor required in repo
NC2000 NOR flash, 16 banks of 32 KiB
- Path:
WQXEmu/nc2000/nc2000.nor - System: wenquxing-nc2000
- Size: min 512.0 KB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:232-237,crates/wqxemu-core/src/machines/nc2000.rs:20,crates/wqxemu-core/src/machines/nc2000.rs:28,crates/wqxemu-core/src/machines/nc2000.rs:265-277 - Read whole from {system}/WQXEmu/nc2000/nc2000.nor in physical order, no bank swap. The image must be at least 16 * 0x8000 bytes or the loader fails; only the first 512 KiB is used. Bank 0 is the fixed BIOS page at 0xE000.
nc2000.nand required in repo
NC2000 NAND flash main area, 65536 pages of 528 bytes
- Path:
WQXEmu/nc2000/nc2000.nand - System: wenquxing-nc2000
- Size: 33.0 MB
- Source:
crates/wqxemu-libretro/src/lib.rs:232-237,crates/wqxemu-core/src/machines/nc2000.rs:22-26,crates/wqxemu-core/src/machines/nc2000.rs:278-282,crates/wqxemu-core/src/machines/nc2000.rs:292-296 - Read whole from {system}/WQXEmu/nc2000/nc2000.nand and copied after the 64-page first plane, up to 65536 pages of 512 data plus 16 spare bytes. No size check: bytes beyond that are ignored and a shorter file leaves the remainder erased at 0xFF.
nc2000.nand0 required in repo
NC2000 NAND flash first plane, 64 pages of 528 bytes
- Path:
WQXEmu/nc2000/nc2000.nand0 - System: wenquxing-nc2000
- Size: 33.0 KB
- Source:
crates/wqxemu-libretro/src/lib.rs:232-237,crates/wqxemu-core/src/machines/nc2000.rs:24,crates/wqxemu-core/src/machines/nc2000.rs:283-288,crates/wqxemu-core/src/machines/nc2000.rs:298-301,crates/wqxemu/src/main.rs:264-269 - Read whole from {system}/WQXEmu/nc2000/nc2000.nand0 into the first 64 pages of the NAND array. No size check. The libretro core always puts it in the NC2000 set and the standalone binary requires --nand0 for this model, so a missing file stops the start.
nc3000.nor required in repo
NC3000 NOR flash, 32 banks of 32 KiB
- Path:
WQXEmu/nc3000/nc3000.nor - System: wenquxing-nc3000
- Size: min 1.0 MB
- Validation: size
- Source:
crates/wqxemu-libretro/src/lib.rs:238-246,crates/wqxemu-core/src/machines/nc3000.rs:23,crates/wqxemu-core/src/machines/nc3000.rs:33,crates/wqxemu-core/src/machines/nc3000.rs:272-284 - Read whole from {system}/WQXEmu/nc3000/nc3000.nor in physical order, no bank swap. The image must be at least 32 * 0x8000 bytes or the loader fails; only the first 1 MiB is used. Bank 0 is the fixed BIOS page at 0xE000.
nc3000.nand required in repo large_file
NC3000 NAND flash, two planes of 65536 pages of 528 bytes
- Path:
WQXEmu/nc3000/nc3000.nand - System: wenquxing-nc3000
- Size: 66.0 MB
- Source:
crates/wqxemu-libretro/src/lib.rs:238-246,crates/wqxemu-core/src/machines/nc3000.rs:25-29,crates/wqxemu-core/src/machines/nc3000.rs:285-289,crates/wqxemu-core/src/machines/nc3000.rs:336-340 - Read whole from {system}/WQXEmu/nc3000/nc3000.nand and copied after the 64-page first plane, up to 131072 pages of 512 data plus 16 spare bytes. No size check: bytes beyond that are ignored and a shorter file leaves the remainder erased at 0xFF.
nc3000.nand0 optional in repo
NC3000 NAND flash first plane, 64 pages of 528 bytes
- Path:
WQXEmu/nc3000/nc3000.nand0 - System: wenquxing-nc3000
- Size: 33.0 KB
- Source:
crates/wqxemu-libretro/src/lib.rs:238-246,crates/wqxemu-core/src/machines/nc3000.rs:27-31,crates/wqxemu-core/src/machines/nc3000.rs:290-297,crates/wqxemu-core/src/machines/nc3000.rs:342-350,crates/wqxemu/src/main.rs:270-274 - Read whole from {system}/WQXEmu/nc3000/nc3000.nand0 into the first 64 pages of the NAND array when the file exists; the libretro core only adds it to the set in that case and the standalone --nand0 is optional for this model. Without it the core writes the marker "ggv nc3000" at offset 528 of an erased first plane and the machine boots the same way.
Generated on 2026-10-10T11:26:02Z