Ingredient
ESP32
Also known as: Espressif ESP32, ESP32-WROOM
Dual-core 32-bit microcontroller-with-radios SoC by Espressif — the default choice for any farm-electronics task that needs WiFi, Bluetooth, or both, and the workhorse of the modern hobbyist IoT pantry. ~240 MHz dual-core Tensilica Xtensa, 520 KB SRAM, 4 MB flash typical, 34 GPIO pins, 18 ADC channels, hardware crypto, deep-sleep current ~10 µA. Programs in Arduino IDE, ESP-IDF, MicroPython, or PlatformIO. ~$5–10 retail per dev board (NodeMCU, DOIT, Adafruit Feather, Heltec). The right ingredient when telemetry needs to leave the field — wireless soil-moisture meshes, MQTT-publishing weather stations, ESP-NOW farm-edge sensor networks.
Inputs / outputs
- GPIO: 34 pins, 3.3V logic (5V tolerant on some inputs but never assume).
- ADC: 18 channels, 12-bit, but non-linear and noisy — calibrate before trusting absolute readings.
- Comms: WiFi 802.11 b/g/n, Bluetooth Classic + BLE, ESP-NOW (Espressif’s low-latency mesh protocol), 3× UART, 2× I²C, 4× SPI.
- Power: 3.3V logic, 5V via USB. Active ~80–240 mA (radio dependent), modem sleep ~15 mA, deep sleep ~10 µA.
Solves / unlocks
- Battery-powered wireless field sensor nodes (deep-sleep + MQTT publish on wake → years on 18650)
- ESP-NOW mesh networks (farm-edge sensor swarms with no WiFi infrastructure)
- Direct integration with [[home-assistant|Home Assistant]] via [[esphome|ESPHome]] (declarative YAML configs, no code)
- Edge-side sensor fusion before publish (filter, compress, threshold)
- BLE provisioning (no need for a screen — phone configures the device)
Constraints
- 3.3V logic — older 5V sensors need level shifters.
- ADC noise — for precision analog work (pH, EC), use an external 16-bit ADC like the ADS1115.
- WiFi power cost — radio bursts dominate the [[energy|energy budget]]; design around deep-sleep.
Source
- Datasheet: https://www.espressif.com/en/products/socs/esp32
- ESP-IDF: https://github.com/espressif/esp-idf (Apache 2.0)
- [[esphome|ESPHome]]: https://esphome.io/ (MIT)
- Arduino-ESP32: https://github.com/espressif/arduino-esp32 (LGPL)
See also
Auto-generated from this entry’s typed relations: frontmatter, grouped by relation type so the editorial signal isn’t flattened.
- Parallels: [[arduino-uno]]
- Member of: [[ingredient]]
- Combines with: [[mqtt]] · [[capacitive-soil-moisture-sensor]] · [[bme280-environmental-sensor]] · [[lorawan]] · [[node-red]] · [[home-assistant]]
What links here, and how
Inbound connections from across the wiki, grouped by lens and by relationship. These appear automatically — every entity page declares what it links to, and that data populates here on the targets.
Practical
parallels
- Arduino Uno ESP32 supersedes Uno when WiFi/Bluetooth or more compute is needed
combines with
- BME280 environmental sensor low-power MQTT-publishing weather node; deep-sleep between reads
- Capacitive soil moisture sensor battery-powered field node; deep-sleep + MQTT publish on threshold cross
- DHT22 temperature-humidity sensor low-cost weather node; replace with BME280 for production
- EC / TDS sensor wireless hydroponic monitoring with MQTT alerting on out-of-range
- ESPHome ESPHome's primary target hardware; no-code firmware authoring
- Home Assistant ESPHome firmware (HA's sister project) turns any ESP32 into a Home Assistant device with no code
- IMU (MPU6050 / BNO085) ESP32 + IMU = wireless tilt/motion node for equipment monitoring
- Leaf wetness sensor wireless orchard / vineyard pest-pressure node
- Lithium BMS (LiFePO₄ battery management) JK / Daly BMS expose Bluetooth or RS485; ESP32 polls and publishes pack telemetry
- LoRaWAN Heltec WiFi LoRa 32 boards bundle ESP32 + RFM95; native LoRaWAN field telemetry
- Meshtastic Meshtastic firmware targets ESP32 + LoRa radio modules (Heltec, T-Beam)
- Modbus / RS-485 ESP32 + RS485 transceiver = wireless gateway to industrial Modbus equipment
- MQTT native MQTT-client libraries (PubSubClient, AsyncMqttClient); the standard ESP32 telemetry pattern
- Node-RED ESP32 publishes MQTT, Node-RED routes and visualizes
- NPK soil probe (RS-485) wireless agronomy node publishing N-P-K-pH-EC over MQTT
- PAR / light sensor wireless DLI logging across a greenhouse or indoor grow
- Peristaltic pump wirelessly-controlled remote-dosing for distributed hydroponic systems
- pH sensor wireless brewing/hydroponic pH alerts
- Servo motor ESP32 PWM is 16-channel, hardware-accelerated; multiple servos with no jitter
- Solar charge controller (MPPT) Victron SmartSolar exposes VE.Direct serial; ESP32 + ESPHome Victron component publishes solar telemetry to Home Assistant
- Solenoid valve wirelessly-controlled valve manifolds; integrate with Home Assistant
contains
- Farm-tech toolkit compute / WiFi+BT microcontroller; default IoT brain
combines
- Recipe: orchard disease-prediction station the field-station compute
- Recipe: closed-loop greenhouse climate controller one or more ESP32s as the field-IO devices in the greenhouse
- Recipe: closed-loop hydroponic doser the publish-observability node, separate from the control MCU
- Recipe: livestock & equipment tracking mesh the compute on each collar (LILYGO T-Beam = ESP32 + LoRa + GPS in one board)
- Recipe: off-grid soil-moisture mesh compute brain of each field node
28 inbound links · 8 outbound