admin writes that multiple independent projects have discovered an undocumented feature in ESP32 chips that bypasses standard WiFi and Bluetooth functions to capture raw IQ baseband samples. This allows several ESP32 models to operate as internal SDRs covering 2.2–2.7 GHz, with the ESP32-C5 extending to 4.8–6.0 GHz at up to 80 MS/s. While most implementations are limited to snapshot-based spectrum analysis due to bandwidth constraints, the new ESP32-S31 supports continuous streaming over Gigabit Ethernet. Other projects have leveraged this feature to enable phase-coherent direction finding and a 5.8 GHz FPV video receiver.
- The ESPARGOS team is not implementing phase-coherent transmissions due to misuse concerns.
- An FPGA-based prototype by user h0m3us3r streams data continuously, though it has poor phase noise.
- The C5VRX project utilizes the undocumented IQ stream for a 5.8 GHz FPV video receiver.
- The ESPARGOS team is not implementing phase-coherent transmissions due to misuse concerns.
- An FPGA-based prototype by user h0m3us3r streams data continuously, though it has poor phase noise.
- The C5VRX project utilizes the undocumented IQ stream for a 5.8 GHz FPV video receiver.
A repository of bug-fixed and patched software projects for DEC PDP-11 systems, targeting real hardware, SimH, and PiDP-11 emulators running RT-11 and RSX-11M-PLUS. The two main projects are FIG-FORTH v1.4, which corrects garbled terminal output and a corrupted screen file, and FOCAL-11 V11-01C, which fixes an infinite recursion crash in the FEXP function.
- FIG-FORTH originally marked dictionary names with a high bit that modern terminals rendered as a literal "?" character; the patch strips it before display without affecting the dictionary
- The FORTH.DAT file was distributed with a VARIABLE RMS record format, embedding 2-byte length headers every 512 bytes that appeared as stray characters in screens
- FOCAL-11's XFEXP computed e^x by recursively halving the exponent until it fell below -8, but zero's exponent never decreases, so the recursion ran the stack into memory; all other math functions already had a depth guard
- FOCAL is a BASIC-like language from the late 1960s; Lunar Lander was originally written in it
- FIG-FORTH originally marked dictionary names with a high bit that modern terminals rendered as a literal "?" character; the patch strips it before display without affecting the dictionary
- The FORTH.DAT file was distributed with a VARIABLE RMS record format, embedding 2-byte length headers every 512 bytes that appeared as stray characters in screens
- FOCAL-11's XFEXP computed e^x by recursively halving the exponent until it fell below -8, but zero's exponent never decreases, so the recursion ran the stack into memory; all other math functions already had a depth guard
- FOCAL is a BASIC-like language from the late 1960s; Lunar Lander was originally written in it
Jenny List writes about how an undocumented feature in certain ESP32 chips allows the raw I/Q stream to be tapped before the WiFi modem, effectively turning them into software-defined radio receivers. Discovered independently by Espargos and a Reddit user, the mode supports both 2.4 and 5 GHz bands but is limited to receive-only operation.
- Only works on ESP32 variants with earlier Tensilica hardware; Bluetooth-only and non-radio P4 chips won't work
- Transmit capability appears possible but remains undocumented, with the discoverer refusing to share due to "rule 3"
- The 80 Msps 32-bit/sample data rate creates bandwidth challenges for external transfer via SDIO or UART interfaces
- Only works on ESP32 variants with earlier Tensilica hardware; Bluetooth-only and non-radio P4 chips won't work
- Transmit capability appears possible but remains undocumented, with the discoverer refusing to share due to "rule 3"
- The 80 Msps 32-bit/sample data rate creates bandwidth challenges for external transfer via SDIO or UART interfaces
Giorgio Mendoza writes that Makerfabs has released the MaTouch ESP32-S3 7.5-inch Quad-Color E-Ink board, pairing an 800×480 four-color electrophoretic display with an ESP32-S3R8 controller, a four-microphone array, a six-axis IMU, and microSD storage for low-power displays and voice-controlled interfaces.
- Priced at $59.80, with an optional OV3660 3-megapixel camera adding $4.80
- The E Ink panel uses a JD79665 controller with a full-screen refresh time of about 20 seconds
- Software support includes ESP-IDF 5.4.2 and Arduino, with published examples for camera capture and voice-activated image browsing
- The board supports 2.4GHz Wi-Fi and Bluetooth 5 LE, with 8MB PSRAM and 16MB SPI flash
- Priced at $59.80, with an optional OV3660 3-megapixel camera adding $4.80
- The E Ink panel uses a JD79665 controller with a full-screen refresh time of about 20 seconds
- Software support includes ESP-IDF 5.4.2 and Arduino, with published examples for camera capture and voice-activated image browsing
- The board supports 2.4GHz Wi-Fi and Bluetooth 5 LE, with 8MB PSRAM and 16MB SPI flash
Maya Posch writes about Aaron Christophel disassembling a €15 UGreen USB-C cable rated at 240 watts, which features an integrated IPS LCD screen and a single touch control. The teardown reveals a PCB with an EN32LF056 Cortex-M0+ MCU, voltage regulators, and a MOSFET for backlighting. By probing the exposed SWD interface, Christophel confirmed the chip has 64 kB of Flash and 4 kB of SRAM, then flashed custom firmware to display video frames on the tiny display.
- The MCU is not wired to the USB data interface, so it cannot act as a man-in-the-middle or keylogger
- A commenter noted that such dense integrated cables raise concerns about secure pairing and encryption for USB connections
- The MCU is not wired to the USB data interface, so it cannot act as a man-in-the-middle or keylogger
- A commenter noted that such dense integrated cables raise concerns about secure pairing and encryption for USB connections
This open-source project provides firmware for an ESP32-C3 Super Mini connected to a 1.28″ round GC9A01 display, creating a sonar-style aircraft radar that visualizes live ADS-B data from adsb.fi around the user's location. The device features WiFiManager for easy initial configuration via a captive portal and allows users to cycle through range presets or reset network credentials using hardware buttons.
- Visualizes aircraft with red heading triangles, magenta speed vectors, and callsign tags.
- Supports runway overlays from major airports based on OurAirports data.
- Displays "rim dots" for approaching aircraft located outside the current radar ring but within range of ADS-B data.
- Uses NVS to persist user settings like latitude, longitude, units (mi/km), and WiFi credentials.
- Visualizes aircraft with red heading triangles, magenta speed vectors, and callsign tags.
- Supports runway overlays from major airports based on OurAirports data.
- Displays "rim dots" for approaching aircraft located outside the current radar ring but within range of ADS-B data.
- Uses NVS to persist user settings like latitude, longitude, units (mi/km), and WiFi credentials.
ppoinha writes a project for the ESP32 Cheap Yellow Display (CYD) that functions as a real-time aircraft tracker, rendering a live radar Plan Position Indicator (PPI) on its 2.8-inch touchscreen. The application displays nearby aircraft details such as callsigns and flight levels, provides weather information via Open-Meteo, and includes a built-in web server for remote configuration of location and search radius.
- Utilizes the ESP32's dual-core architecture to handle API calls on Core 0 while maintaining smooth UI rendering on Core 1.
- Integrates data from OpenSky Network for ADS-B states and hexdb.io for ICAO route lookups.
- Features a scrollable list of the five closest flights along with real-time system statistics like WiFi RSSI and free RAM.
- Utilizes the ESP32's dual-core architecture to handle API calls on Core 0 while maintaining smooth UI rendering on Core 1.
- Integrates data from OpenSky Network for ADS-B states and hexdb.io for ICAO route lookups.
- Features a scrollable list of the five closest flights along with real-time system statistics like WiFi RSSI and free RAM.
Tom Nardi writes that Mateusz Juszczyk has created a desktop gadget called ESP32-Plane-Radar, which uses an ESP32-C3 Super Mini and a round GC9A01 display to visualize aircraft movement. Rather than using actual radar hardware, the device connects via WiFi to adsb.fi to pull crowdsourced Automatic Dependent Surveillance–Broadcast (ADS-B) flight data, creating a professional-looking circular radar display that reflects real-world local airspace activity.
- The project features a minimalistic 3D printed enclosure for its components.
- A web-based configuration interface is included for easier setup via WiFi.
- Despite the name, it does not sniff ADS-B signals directly from radio waves but uses internet data instead.
- The project features a minimalistic 3D printed enclosure for its components.
- A web-based configuration interface is included for easier setup via WiFi.
- Despite the name, it does not sniff ADS-B signals directly from radio waves but uses internet data instead.
socquique writes of Capsule Radar, a live ADS-B aircraft radar designed for the Waveshare ESP32-S3-Touch-AMOLED series (1.75 and 1.43 inch round displays). The software pulls real-time flight data via WiFi to plot nearby aircraft on various visual themes like Phosphor or Orb, offering touch interaction for detailed flight information such as routes and altitude.
- Supports browser-based flashing via ESP Web Tools
- Includes a native SDL2 desktop simulator for testing without hardware
- Features automated route lookups using adsbdb
- Provides "face-down" sleep mode triggered by the onboard IMU
- Compatible with Waveshare's 1.75 and 1.43 AMOLED boards
- Supports browser-based flashing via ESP Web Tools
- Includes a native SDL2 desktop simulator for testing without hardware
- Features automated route lookups using adsbdb
- Provides "face-down" sleep mode triggered by the onboard IMU
- Compatible with Waveshare's 1.75 and 1.43 AMOLED boards
Alex-developer writes about a standalone aircraft radar firmware designed for Waveshare ESP32-P4 round touch displays. The system connects to WiFi to fetch live ADS-B traffic, visualizing it on 3.4-inch or 4-inch screens with features like range rings, altitude color coding, airport markers, and weather overlays. It operates independently without needing a Raspberry Pi or an active browser once configured via its built-in admin web page or touch interface.
- Supports both the 720x720 (4") and 800x800 (3.4") Waveshare LCD variants from a single firmware image
- Integrates with multiple data sources including Airplanes.live, ADSB.lol, and local feeds like readsb/dump1090
- Features an optional web-based admin interface for configuration of location, display settings, and WiFi
- Can include aircraft detail popups with PlaneSpotters photo thumbnails via touch input
- Supports optional hardware additions such as a USB GPS receiver or a secondary SSD1306 status OLED
- Supports both the 720x720 (4") and 800x800 (3.4") Waveshare LCD variants from a single firmware image
- Integrates with multiple data sources including Airplanes.live, ADSB.lol, and local feeds like readsb/dump1090
- Features an optional web-based admin interface for configuration of location, display settings, and WiFi
- Can include aircraft detail popups with PlaneSpotters photo thumbnails via touch input
- Supports optional hardware additions such as a USB GPS receiver or a secondary SSD1306 status OLED
