The pocket station: XIAO ESP32-C6 + BME680

One postage-stamp computer, one sensor, four wires — temperature, humidity, pressure and a VOC air-quality index, live on the map.

The wiring

XIAO 3V3 → sensor VCC     (power — never the 5V pin)
XIAO GND → sensor GND     (ground)
XIAO D4  → sensor SDA     (data,  GPIO22)
XIAO D5  → sensor SCL     (clock, GPIO23)
SDO and CS on the sensor stay EMPTY (that selects I²C address 0x77)

The software

Arduino IDE with the esp32 boards package (3.0+), board XIAO_ESP32C6, libraries Adafruit BME680, Adafruit Unified Sensor and ArduinoJson. The firmware itself comes pre-configured from your device's ⚙ Manage → Flash firmware panel on sensormap.cloud.

Download the full illustrated guide (PDF) →

Twelve pages: labeled pinouts, breadboard layout, soldering tips, the SensorMap walkthrough, placement advice for honest readings, and a troubleshooting table for every "NOT FOUND" we know about.