M5Stack ENV IV Unit (SHT40 + BMP280)
A precision environmental sensor in one tiny unit: temperature, humidity, and barometric pressure on a single Grove I2C port.
Say it to PAL
“Keep a log of everything it measures about the air.”
The code PAL writes
const t = await p.read('m5-env4', 'temperature');
const h = await p.read('m5-env4', 'humidity');
const pr = await p.read('m5-env4', 'pressure');
p.log(`${t}°C, ${h}% RH, ${pr} hPa`);“Tell me when the air gets too humid.”
The code PAL writes
p.onSensorChange('m5-env4', 'humidity', (rh) => {
if (rh > 70) p.notify('High humidity: ' + rh + '%');
});
await p.waitUntilStopped();When to pick it
Pick this when you need accurate temperature AND humidity AND barometric pressure together. If you only need temp/humidity, a plain SHT40 is cheaper; if you need air quality, choose a gas-sensor unit.
Good to know
- BMP280 die temperature runs warmer than ambient; trust the SHT40 for room temperature, not the barometer's internal temp.
- Humidity needs airflow — don't seal the unit in a tight enclosure or readings lag and read high.
About it
The M5Stack ENV IV combines a Sensirion SHT40 (±0.2 °C / ±1.8% RH high-precision temperature & humidity) with a Bosch BMP280 barometric pressure sensor on one Grove I2C connector. It is a two-chip unit — the SHT40 answers at 0x44 and the BMP280 at 0x76 — making it a complete weather/climate station for greenhouses, rooms, and outdoor logging, with pressure usable for weather trends and relative altitude.
Where to buy
Facts
Tested
It is in our catalog, but nobody has checked it on a real board. It may not work yet. Its driver is written, but it has not been tested on hardware yet.
I2C address
The M5Stack ENV IV Unit (SHT40 + BMP280) uses I2C addresses 0x76 and 0x44 at once, one for each of its chips. These addresses are fixed.
Board size
32 × 24 mm
The ENV IV board measures 32 × 24 mm and stands 8 mm tall with its parts. It has 2 mounting holes. These dimensions are from the maker’s mechanical drawing.
Chips
SHT40, BMP280
Its sensor is the Sensirion SHT40. Its sensor is the Bosch BMP280.
Free to reuse
Every fact here is open data under CC BY 4.0. Copy it into your own docs or code, and credit Palpable. Download it
This record was last changed on October 7, 2026.