M5Stick-C Wi-Fi Spectrum Explorer (and SSID Tracker)

I built a small firmware project for the M5Stick-C that continuously scans the 2.4 GHz Wi-Fi band, visualizes channel congestion as a histogram, and lets you drill into the strongest nearby networks (SSID, RSSI, channel). There’s also a lightweight tracking mode that estimates distance to a selected SSID using RSSI.

Pocket-sized Wi-Fi visibility: quick scans and a clear spectrum view on the M5Stick-C.

What it does

• Periodic active scans of nearby Wi-Fi networks across channels 1–13.
• Histogram “spectrum” view showing how congested each channel is.
• Detail view listing the strongest networks with RSSI (dBm) and channel.
• Manual rescan on demand.
• Battery indicator with live percentage on screen.
• Tracking mode: lock onto an SSID and display RSSI + estimated distance.

Spectrum view (channel congestion)

The default screen is a simple histogram across channels 1–13. It gives an at-a-glance picture of where the band is crowded, so you can quickly spot quieter channels.

Spectrum view: channel congestion histogram (2.4 GHz, channels 1–13).

Detail view (SSID / RSSI / channel)

Press Button A to open the network list. Scanning pauses so the list stays stable while browsing. The firmware shows the strongest networks with RSSI (dBm) and channel.

Detail view: strongest SSIDs with RSSI (dBm) and channel.

Tracking mode (follow a selected SSID)

From the detail list, long-press Button B to lock onto the highlighted SSID and enter tracking. This view refreshes faster and shows the current RSSI plus an estimated distance.

Tracking view: live RSSI updates + distance estimate for the selected SSID.

Build & flash (PlatformIO)

python -m platformio run
python -m platformio run --target upload

Source code

GitHub: https://github.com/error0327/M5STICK-C-Wifi-Tracker

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Suggested Blogger labels: ESP32, M5StickC, PlatformIO, WiFi, IoT, Embedded, Maker