SubCensusEsp — Web Flasher

Before you flash

Wire the CC1101 to the ESP32 (see the wiring below). You can flash the bare board first and wire the radio after — the firmware boots fine without it (the web UI shows cc1101: absent until it's connected).
Plug the ESP32 into your computer with a data-capable USB cable (many cheap cables are charge-only and won't enumerate a serial port).
Install the USB-UART driver for your board if needed: CP210x (most WROOM devkits) or CH340.
Close any other program using the serial port (Arduino IDE / PlatformIO monitor / screen).
Click Install SubCensusEsp above, pick your board's serial port, and confirm. The flasher erases the chip and writes firmware + the web-UI filesystem (~1 min).

The button flashes a merged image (bootloader + partitions + app + LittleFS web UI) built by CI from the exact firmware in the repo, so the flasher and the source never drift.

Wiring the CC1101

The CC1101 talks to the ESP32 over the VSPI hardware bus. Capture rides GDO0 (hardware RMT edge-timing), independent of WiFi/web activity.

3.3 V only. The CC1101 is a 3.3 V part — power it from the ESP32 3V3 pin, never 5 V / VIN. Logic is 3.3 V on both sides, so no level shifter is needed.

CC1101 ⇄ ESP32 over VSPI. GDO2 (→ GPIO 35) is optional. GPIO 34 is input-only — perfect for GDO0 edge capture.

Pin map

CC1101	ESP32 GPIO	Purpose
VCC	3V3	3.3 V only — not 5 V
GND	GND	Ground
SCK	18	VSPI clock
MOSI (SI)	23	VSPI data to radio
MISO (SO)	19	VSPI data from radio
CSN (CS)	5	Chip select
GDO0	34	RX data / RMT edge capture (input-only pin)
GDO2	35	Optional (input-only)
ANT	—	Antenna tuned to your band (~433 or ~915 MHz)

Module pin labels vary. On 8-pin SPI modules, SI = MOSI and SO = MISO. Some boards silk-print GD0/GD2 for GDO0/GDO2. Keep SPI wires short; solder a whip/coil antenna to ANT for real range.

Avoid strapping pins. The map deliberately steers clear of GPIO 0/2/12/15. GPIO 34/35 are input-only (fine for the GDO capture/status lines).

First boot & setup

After flashing, the node reboots and starts serving its UI over WiFi (Esp §5).
With no WiFi credentials yet, it brings up a setup access point named SubCensusEsp-setup. Join it, then set your WiFi in the node's Settings page, or set credentials over serial.
Open the Serial monitor at 115200 baud to see boot logs and the assigned IP:
SC boot node=subcensusesp
SC cc1101 present=1 version=0x14
SC core_ok crc=180 place=home
Browse to the node's IP to reach the full UI: Live feed, Review/label, Bands (occupancy/watchlist), Places, and Settings.
No radio wired yet? Try the built-in fixture path: POST /api/recon with action=fixture populates a demo occupancy/watchlist, and POST /api/debug/inject replays a .sub capture through the full decode → classify → log → live-feed pipeline — no RF needed.

Monitoring is passive. Sweep/Camp/Recon never transmit. TX (replay / edit-before-transmit) is off by default and TX-allow-list gated.

Troubleshooting

No port in the picker	Use a data USB cable; install the CP210x/CH340 driver; try another USB port.
"Failed to initialize"	Close other serial monitors, unplug/replug, retry. On some boards hold BOOT while the flash starts, release after it connects.
Button missing / greyed	You're not on Chrome/Edge desktop. Web Serial isn't in Firefox, Safari, or mobile browsers.
cc1101: absent in the UI	Check 3V3 power, CS→GPIO5, and the SPI wiring; a floating VERSION register reads absent.
Flashes but no WiFi	Join SubCensusEsp-setup and set credentials, or set them over serial; watch the monitor for the IP.