v6.0 is the feature release that turns the beacon from a transmitter with a scanner into a full radio tool: it can now also listen and decode incoming Morse in real time, report its own battery and temperature, and draw the received signal as an oscilloscope-style trace.

LISTEN mode and the CW decoder

The headline feature. MODE LISTEN keeps the radio on the first configured frequency and runs a real-time Morse CW decoder:

RSSI is sampled every 5 ms (CW_SAMPLE_MS).
A carrier is a mark when RSSI is at or above the configured rssiThreshold.
Mark and gap durations are measured with the same PARIS timing model the transmitter uses (unit = 1200 / WPM ms).
Marks of at most 2 units decode as dots, longer marks as dashes.
Gaps of at least 3 units end a character, gaps of at least 7 units end a word.
Full ITU table: A-Z, 0-9, punctuation (. , ? - ” / ! + = @ $ ( )).
Decoded characters stream to the OLED (two-line window) and over USB serial as one AEGIS:CW:<char> line each; the blue LED blinks on every character.

Enter it with MODE LISTEN over serial or from a scripted bridge command. MODE short-press returns to BEACON, SEL long-press enters CONFIG. See LISTEN mode for the full screen and operating details and Firmware CW decoder for the timing internals.

Battery monitor, live

The firmware now really measures the pack: a 2:1 resistor divider on GPIO 36 (ADC1, so it keeps working while WiFi uses ADC2) is sampled every 5 seconds:

readBatteryMv() returns the pack voltage in millivolts.
battPct() maps 3300-4200 mV linearly to 0-100%.
A battery glyph appears on BEACON, SEARCH and LISTEN screens with three level cells.
Below 3550 mV (BATTERY_LOW_MV) the glyph flashes, the red LED blinks four times and AEGIS:BATT:low;mv=.. is printed once; the warning resets when the voltage recovers.
BATT serial command replies AEGIS:BATT:mv=..;pct=...

Board temperature

The ESP32 internal silicon sensor is read with temperatureRead() and reported as temp= in the extended AEGIS:STATE line and in the serial STATUS block. Values outside 1-125 °C are reported as 0.0 (sensor unavailable).

RSSI history strip-chart

SEARCH and LISTEN screens now draw the last 120 RSSI samples (RSSI_HIST_LEN) as a strip-chart trace instead of a plain fill bar. The threshold tick stays, and a sweeping caret shows the scanner is actively looking while no signal is detected.

OLED engine rework

Every screen was redrawn with shared vector glyphs: pulsing antenna arcs (BEACON/LISTEN headers, splash), a satellite glyph and 4-cell lock meter (GPS WAIT), a segmented TX progress bar with a blinking caret, distress corner brackets and a blinking TX light (EMERGENCY), a WiFi glyph and checklist (CONFIG), and centered message dialogs with a double frame.

Serial protocol extensions

Line	Example	Meaning
`AEGIS:BATT:`	`AEGIS:BATT:mv=3710;pct=52`	Battery voltage and percentage
`AEGIS:BATT:low;mv=..`	`AEGIS:BATT:low;mv=3510`	Low-battery warning (once per drop)
`AEGIS:CW:<char>`	`AEGIS:CW:S`	One line per decoded Morse character
`AEGIS:STATE`	`...;batt=3710;temp=42.1;up=312`	`STATUS` now appends battery, temperature, uptime
`AEGIS:HELLO`	`ver=6.0;...`	Version bumped

Upgrading

Flashing v6.0 over v5.5 is safe: the NVS schema is unchanged, so every setting (frequencies, WPM, message, mode, thresholds) is preserved. If you want to try LISTEN mode immediately, flash, then send MODE LISTEN from the serial monitor or the bridge TUI.