# BayCom/based · MAX25-Stack

Public mark: **BayCom/based**. Product path: **max25-bcpr** (daemon **max25-bcprd**, ctl **max25-bcpr-ctl**). Host device: **`max25e0`** (forks `max25e0:bcN` only).

## Status: available and usable

| Fact | Value |
|------|--------|
| Product status | **Available** — shipped operator path with HyBBX co-host |
| Default build | `MAX25_BUILD_MAX25_BCPR=ON` |
| Device id | **`max25e0`** only |
| KISS release | **`/tmp/max25-bcpr/kiss-bc0`** — HyBBX opens after max25d prep |
| Attach modes | `hybbx-host` · `hybbx-main` · `hybbx-cohost` — max25d releases KISS to HyBBX |
| Host addresses | IPv4 `127.0.0.25/8`, IPv6 `::25/128` (defaults; overridable in `max25d.ini`) |
| Kernel path | `baycom_ser_fdx` / `baycom-pr` **removed** — userspace **max25-bcpr** only |

## Start (with HyBBX co-host)

```bash
# max25d with mode=hybbx-cohost and [features] max25_bcpr=yes
./scripts/run-max25d.sh
ls -la /tmp/max25-bcpr/kiss-bc0    # KISS PTY after max25-bcpr ready
# then HyBBX with [networks] baycom=yes, device=/tmp/max25-bcpr/kiss-bc0
```

Example INI: `share/max25-bcpr/max25-bcpr.ini.example` · `share/hybbx/hybbx-standalone.ini.example` (HyBBX repo).

## Operator rules

| Rule | Detail |
|------|--------|
| RX before TX | Prove RX (Soft-DCD / decode) before live TX |
| Serial ownership | One process per UART — max25d prep then HyBBX attach |
| HyBBX user | Must be in group `dialout` for KISS PTY |

Development freeze notes: [BAYCOM-FREEZES.md](BAYCOM-FREEZES.md) — not part of normal operator path.

## Build

```bash
cmake -B build -DMAX25_BUILD_MAX25_BCPR=ON   # default ON in release preset
cmake --build build --target max25-bcprd max25-bcpr-ctl
```

## Related

| Goal | Doc |
|------|-----|
| Device model | [PLUGINS-DEVICE-MODEL.md](PLUGINS-DEVICE-MODEL.md) |
| TX/RX test | [TX-RX-TEST.md](TX-RX-TEST.md) |
| HyBBX attach | HyBBX [docs/BAYCOM.md](../../hyBBX/docs/BAYCOM.md) |
| TNC / modem bring-up | [DEV/TNC-MODEM-DEV.md](DEV/TNC-MODEM-DEV.md) |