afiqzudinhadi
2af45eafce
Full steno engine: chord detection, MPHF/trie dict lookup, Plover formatter (18 commands), undo (ring buffer), HID + Unicode output. Split-storage specific: - BLE GATT service for dict queries (query/prefix/batch) - LRU cache on central side (CONFIG_STENO_SPLIT_CACHE_SIZE) - Dict embedded on peripheral, engine runs on central - 3-way dispatch: split_dict / MPHF / simple trie Build system: auto-fetch Plover dict, MPHF compiler with block compression (~56K entries in 420KB), CMake integration.
1.3 KiB
1.3 KiB
zmk-steno-engine
Clean-room steno engine for ZMK keyboards. Split-storage architecture: full dictionary on peripheral (right) half, queried over BLE from central (left) half.
Status: Early development — not yet functional.
Architecture
ZMK splits run two nRF52840 halves connected via BLE. The right (peripheral) half has ~533KB free flash — enough for a full steno dictionary. The left (central) half runs the steno engine.
┌─────────────┐ BLE GATT query ┌──────────────┐
│ Left half │ ───────────────► │ Right half │
│ (central) │ ◄─────────────── │ (peripheral) │
│ │ translation │ │
│ Steno engine│ │ Dictionary │
│ LRU cache │ │ (~533KB) │
└─────────────┘ └──────────────┘
Key design decisions:
- Dictionary stored on peripheral → no flash pressure on central
- BLE GATT custom service for stroke→translation queries
- LRU cache on central side → reduces BLE round-trips for common words
- Orthographic rules run on central after dictionary lookup