Add successive MFSK-8, MFSK-16, and MFSK-32/R modes, misc fixes

CONTROL_PORT.md

@@ -0,0 +1,119 @@
+# Control Port API
+
+TCP JSON protocol on port 8073 
+
+Wire format: 4-byte big-endian length prefix + JSON payload.
+
+## Commands
+
+| Command | Description |
+|---|---|
+| `get_status` | Current modem/channel state |
+| `get_config` | Current configuration |
+| `set_config` | Update configuration (partial updates OK) |
+| `rigctl` | Passthrough command to rigctld |
+| `tx` | Transmit data via KISS |
+
+---
+
+## `get_status`
+
+**Request:** `{"cmd": "get_status"}`
+
+**Response:**
+
+| Field | Type | Description |
+|---|---|---|
+| `channel_state` | string | `"idle"`, `"tx"`, or `"rx"` |
+| `ptt_on` | bool | PTT currently keyed |
+| `rx_frame_count` | int | Successfully decoded frames |
+| `tx_frame_count` | int | Transmitted frames |
+| `rx_error_count` | int | Preamble + CRC errors |
+| `sync_count` | int | Preamble sync detections |
+| `preamble_errors` | int | Sync found but preamble decode failed |
+| `symbol_errors` | int | Symbol-level errors (OFDM only) |
+| `crc_errors` | int | CRC check failures |
+| `last_snr` | float | Last decoded frame SNR (dB) |
+| `last_ber` | float | Last decoded frame BER (0.0-1.0, -1 if unavailable) |
+| `ber_ema` | float | Exponential moving average BER |
+| `client_count` | int | Connected KISS clients |
+| `rigctl_connected` | bool | rigctld connection status |
+| `audio_connected` | bool | Audio device health |
+
+Stats switch between OFDM and MFSK decoder based on active `modem_type`.
+
+---
+
+## `get_config`
+
+**Request:** `{"cmd": "get_config"}`
+
+**Response:**
+
+| Field | Type | Description |
+|---|---|---|
+| `callsign` | string | Station callsign |
+| `modem_type` | int | `0` = OFDM, `1` = MFSK |
+| `mfsk_mode` | int | `0` = MFSK-8, `1` = MFSK-16, `2` = MFSK-32, `3` = MFSK-32R |
+| `modulation` | string | OFDM: `"BPSK"`..`"QAM4096"`. MFSK: `"MFSK-8"`..`"MFSK-32R"` |
+| `code_rate` | string | `"1/2"`, `"2/3"`, `"3/4"`, `"5/6"`, `"1/4"` (OFDM only) |
+| `short_frame` | bool | Short frame mode (OFDM only) |
+| `center_freq` | int | Center frequency in Hz |
+| `payload_size` | int | Current PHY payload capacity in bytes |
+| `csma_enabled` | bool | CSMA carrier sense enabled |
+| `carrier_threshold_db` | float | CSMA threshold (dB) |
+| `p_persistence` | int | P-persistence value (0-255) |
+| `slot_time_ms` | int | CSMA slot time (ms) |
+| `tx_blanking_enabled` | bool | Suppress decoder during TX |
+
+---
+
+## `set_config`
+
+**Request:** `{"cmd": "set_config", ...fields...}`
+
+Send only the fields you want to change. All fields from `get_config` are accepted.
+
+
+Example:
+```json
+{"cmd": "set_config", "modulation": "8PSK", "code_rate": "1/2"}
+```
+
+**Response:** `{"ok": true}` or `{"ok": false}`
+
+---
+
+## `rigctl`
+
+**Request:** `{"cmd": "rigctl", "command": "F"}`
+
+Passes the command string to rigctld and returns the response.
+
+**Response:** `{"ok": true, "response": "145000000\n"}`
+
+---
+
+## `tx`
+
+**Request:**
+```json
+{"cmd": "tx", "data": "<base64-encoded payload>", "oper_mode": -1}
+```
+
+| Field | Type | Description |
+|---|---|---|
+| `data` | string | Base64-encoded raw payload bytes |
+| `oper_mode` | int | OFDM mode override (-1 = use current config) |
+
+**Response:** `{"ok": true, "size": 123}`
+
+---
+
+## Events
+
+The control port broadcasts  events to all connected clients:
+
+| Event | When |
+|---|---|
+| `config_changed` | Any configuration change  |