7. Subject Area Model (APP 408)

7.1 Subject Areas

Subject Area Model

7.2 Entity Definitions

Entity Attributes Description
ClientSession websocket, channel_type, connected_at Runtime connection in ctrl_clients, spectrum_clients, audio_rx_clients, audio_tx_clients
RadioConnection serial_port, baudrate, connected, model_id CAT serial port state within CatController
RadioState vfo_a_freq, vfo_b_freq, active_vfo, mode, tx_status, s_meter, af_gain, rf_gain, rf_power, filter_width, preamp, attenuator, noise_blanker, noise_reduction, auto_notch, compressor, compressor_level, nr_level, nb_level, tuner_status, power_on, squelch, mic_gain, split, vox, break_in, comp_meter, alc_meter, power_meter, swr_meter, id_meter, vd_meter, scope_span, scope_speed, scope_mode, scope_start_freq, serial_connected Dataclass with dirty-field tracking
CatCommand prefix, value, response Serial CAT command: send "FA014200000;" → receive "FA014200000;"
ScopeFrame wf1[850], wf2[850], s_meter, vfoa_freq, mode, scope_span, scope_mode, preamp, attenuator, scope_start_freq Parsed from scope_pipe stdout payload
SpectrumFrame version_byte, wf1_bytes[850], wf2_bytes[850] Binary frame broadcast via /WSspectrum
AudioChunk pcm_bytes, sample_count, timestamp Raw Int16 PCM from PyAudio capture
AudioFrame tag_byte, payload_bytes Tagged dual-codec frame (0x00=PCM, 0x01=Opus) broadcast via /WSaudioRX
OpusEncoder bitrate, frame_size, cap_bytes Server-side libopus encoder via ctypes
OpusDecoder sample_rate, channels WASM Opus decoder in browser
PollTier interval, commands, fields One tier of the 7-task polling scheduler
MemoryChannel index, frequency, mode, label Memory record persisted in mem_channels.json
AuthToken token_hex, created_at 32-byte random hex session token
SCOPE_PIPE_Process pid, stdout, stderr Subprocess running scope_pipe.py for FT4222 SPI I/O

7.3 Relationships

Relationship Cardinality Description
ClientSession → RadioState N:1 Multiple browsers see same state via broadcast
CatCommand → RadioState 1:1 Each CAT response updates one or more state fields
ScopeFrame → SpectrumFrame 1:1 Each parsed scope frame produces one spectrum frame
AudioChunk → AudioFrame 1:N One PCM chunk may produce multiple Opus frames (20ms boundaries)
RadioState → ClientSession 1:N Dirty-field state updates fan out to all ctrl_clients
PollTier → CatCommand 1:N Each tier sends multiple CAT queries per cycle

7.4 State Ownership

State Owner Persistence
Connected WebSockets server.py global sets Runtime only
Radio state RadioState dataclass Runtime only
CAT connection CatController instance Runtime only
Scope data ScopeHandler instance Runtime only
Audio streams AudioHandler instance Runtime only
Poll schedule PollScheduler instance Runtime only
Memory channels /api/mem_channels + mem_channels.json Filesystem (JSON)
Auth tokens _auth_tokens set Runtime only (cleared on restart)
UI state radioState object, DOM Browser session/cookies
Waterfall pixels Canvas image data Browser runtime only