Supported Hardware - mitra42/frugal-iot GitHub Wiki
List of Development Boards; Sensors and Actuators tested
Note that for most parts, we have listed a supplier - usually the one for the unit tested, and restricted to AliExpress "Choice" so it includes shipping. Prices fluctuate, so a search on aliexpress or elsewhere may turn up cheaper parts - especially if buying in quantity.
Development boards
| EURO | Processor | I2C socket | Antenna socket | Color LED | Battery | LoRa | OLED | ||
|---|---|---|---|---|---|---|---|---|---|
| D1 Mini V4 | €1.76 | ESP8266 | N | N | N | N | N | N | |
| C3 Pico | €5.30 | ESP32 | Y | N | Y | Y | N | N | |
| C3 Supermini | [€1.47)[https://www.aliexpress.com/item/1005007729799179.html] | ESP32 | N | N | Y | N | N | N | |
| SX C3 OLED | [€3.34)[https://www.aliexpress.com/item/1005008079598101.html] | ESP32 | N | N | ? | N | N | 0.42" | |
| D1 pro V3 | €3.64 | ESP8266 | N | Y | N | N | N | N | (blue) Add antenna for €0.53 |
| D1 pro V2 | €6.63 | ESP8266 | Y | Y | N | Y | N | N | (green) Add antenna for €0.53 |
| Node MCU Wroom32 | €3.57 Rs343 | ESP32 | N | N | N | N | N | N | Tested by GDT |
| S2 Mini V1 | €2.45 | ESP32 S2 | N | N | N | N | N | N | Lots of GPIO (including A2D and D2A) |
| Lilygo T3 S3 | €20.04 | ESP32 S3 | Y | Y | N | Y | Y | Y | |
| Lilygo TTGO | €19.17 | ESP32 S3 | Y | Y | N | Y | Y | Y | |
| Heltec V3 | €21.88 | ESP32 S3 | N | Y | N | Y | Y | Y | Has a really nice case |
Which to choose ....
- For absolute budget, I would until recently have suggested D1 Mini V4, but C3 boards like the Supermini are edging them out.
- If WiFi range is the concern then the D1 Mini Pro V3 clone
- If you need lots of ports then the S2 Mini V1
- If you want the plug and play of a I2C port (for developing) I prefer the C3 Pico.
- If your devices need to be out of range of WiFi and mesh to a gateway (via LoRa) choose the LilyGo T3S3 or Heltec, they are similar and the Heltec has the advantage of a nice 3D-printed case which may work well.
Sensors
| Measures | Device | Const | Interface | Notes |
|---|---|---|---|---|
| Temperature & Humidity | SHT30 | see below | I2C | |
| Temperature & Humidity | SHT40 | see below | I2C | |
| Temperature & Humidity | DHT11 | €1.46 | OneWire | |
| Temperature & Humidity | DHT22 | €1.55 | OneWire | |
| Temperature | DS18B20 | €0.74 | OneWire | |
| Air Quality (TVOC, eCO2, AQI, Temp, Humidity) | ENS160+AHT21 | €3.04 | I2C | |
| Soil moisture (capacative) | €0.74 | Analog | ||
| Light | BH1750 | €1.28 | I2C | |
| Battery | Analog | |||
| Buttons | switches | Digital debounced | ||
| Load Cell | HX711 2kg | €1.69 | Custom | Single load sensor |
| Load Cell | HX711 200kg | €4.29 | Custom | Get the version with the brackets |
SHT - Temperature and Humidity Sensors
So far I've tested and like - for different reasons - 3 SHT30 and 1 SHT40 sensor.
| Sensor | Purchase | Connection | I2C Addr | Protected | Notes |
|---|---|---|---|---|---|
| Lolin SHT30 shield | €3.38 | Shield or Socket | 0x45 | No | Standard shield, good for developing |
| SZHJW SHT30 | SHT30-D for €0.90 | holes | 0x44 | No | Cheapest I have found |
| Protected SHT30 | ~€0.83 at 10x | 1 metre cable | 0x44 | Yes | Really nice for remote probe or through wall - multiple suppliers, shop around |
| Protected SHT40 | €1.56 | 1 metre cable | 0x44 | Yes | |
| Waterproof DS18B20 | €0.74 at 10x | 1 meter cable | OneWire | Yes | Only does temperature, but waterproof |
Next up: Not necessarily in this order:
Air Quality: SGP30; UV GUVA-S125D 3528; **Pressure(( MS5803; GPS ATGM336H; Soil Resistive; Salinity; Temperature/Humidity/Pressure AHT20+BHP280 ; BMP180
Actuators
| Cost | ||
|---|---|---|
| Relay shield | 2.67 | |
| Monochrome LED | built in |
Next Up (not necessarily this order); RGB LEDs
Reprogrammed complete devices
| Cost | ||
|---|---|---|
| Sonoff Basic R2 | €4 | Simple mains relay, easily wired into lights, fans etc Programming details Issue 108 |
| Sonoff Basic R4 | €5.66 | The ESP32 version of the Sonoff |
| LilyGo Higrow | €10 (€16 with case) | Plant control - including BH1750; DHT11; Switches; Capacitive Soil; Motor/pump Control |