Drop FX.25 for now

README.md

@@ -0,0 +1,71 @@
+# ax25.js — AX.25 + HDLC utilities (TypeScript)
+
+This repository provides low-level utilities for AX.25 frame construction/parsing and HDLC framing used in amateur radio applications. It's intentionally small and focused on framing, FCS and control-field helpers.
+
+## Highlights
+
+- `Address` – create and parse callsigns, produce 7-byte AX.25 address fields.
+- `Frame` – `InformationFrame`, `SupervisoryFrame`, `UnnumberedFrame` and `Frame.fromBytes()` parsing.
+- Control builders: `buildIControl`, `buildSControl`, `buildUControl` (and extended 2‑byte builders).
+- Encoders: `encodeFrame`, convenience `encodeAx25` / alias `encodeAX25`.
+- HDLC: `encodeHDLC`, `escapeBuffer`, `unescapeBuffer`, `computeFcs` / `crc16Ccitt`, `verifyAndStripFcs`.
+- Convenience stream helpers: `toHDLC`, `toWire`, `toWireStream`.
+- `FX25` class: detection heuristics; full FEC decoding (Reed–Solomon) is a TODO.
+
+## Install & tests
+
+```bash
+npm install
+npm test
+```
+
+## Examples
+
+Note: during development you can import directly from `src/*`. When published, import from the package entrypoint.
+
+### Address
+
+```ts
+import { Address } from './src/address';
+
+const a = Address.fromString('N0CALL-0');
+console.log(a.toString()); // N0CALL-0
+```
+
+### Build an AX.25 UI payload and HDLC-wrap it
+
+```ts
+import { Address } from './src/address';
+import { UnnumberedFrame, encodeFrame, encodeAX25, toHDLC } from './src/frame';
+
+const src = Address.fromString('SRC-1');
+const dst = Address.fromString('DST-0');
+const info = new TextEncoder().encode('payload');
+
+// quick builder
+const ax = encodeAX25(dst, src, info, { ui: true });
+
+// or construct Frame and HDLC-wrap
+const f = new UnnumberedFrame(src, dst, 0x03, 'UI', 0, info);
+const hdlc = toHDLC(f); // includes FCS, escapes and flags
+```
+
+### Parsing
+
+```ts
+import { Frame } from './src/frame';
+
+const frame = Frame.fromBytes(ax);
+console.log(frame.toString());
+```
+
+## HDLC & FCS
+
+- `computeFcs(payload)` — CRC-16-CCITT with AX.25/X.25 inversion semantics.
+- `encodeHDLC(payload, { includeFcs: true })` — wraps payload with 0x7E flags, appends FCS and escapes special bytes.
+- `verifyAndStripFcs(buf)` — validates and strips a little-endian 2-byte FCS from a buffer.
+
+## Testing and style
+
+- Tests live in `test/` and are run with Vitest. They follow `describe('Class.method', ...)` naming.
+- Keep tests targeted and add coverage for new behavior.