---
name: "lmenv"
section: "4"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/lmenv"
---

# lmenv(4)

National Semiconductor LM87 temperature, voltage, and fan sensor

## NAME

**lmenv** – National Semiconductor LM87 temperature, voltage, and fan sensor

## SYNOPSIS

**lmenv\* at iic?**

## DESCRIPTION

The **lmenv** driver provides support for the National Semiconductor LM87, National Semiconductor LM81, Analog Devices ADM9240, and Dallas Semiconductor 1780 temperature sensors. The sensor possesses a collection of sensor values which are made available through the [sysctl(8)](/sysctl/8.md) interface:

```
$ sysctl hw.sensors.lmenv0
hw.sensors.lmenv0.temp0=-128.00 degC (External)
hw.sensors.lmenv0.temp1=29.00 degC (Internal)
hw.sensors.lmenv0.fan0=3220 RPM
hw.sensors.lmenv0.volt0=2.62 V DC (+2.5Vin)
hw.sensors.lmenv0.volt1=1.49 V DC (Vccp)
hw.sensors.lmenv0.volt2=3.28 V DC (+Vcc)
hw.sensors.lmenv0.volt3=5.03 V DC (+5Vin/Vcc)
hw.sensors.lmenv0.volt4=12.00 V DC (+12Vin)
hw.sensors.lmenv0.volt5=1.20 V DC (Vccp)
```

## SEE ALSO

[iic(4)](/iic/4.md), [intro(4)](/intro/4.md), [sensorsd(8)](/sensorsd/8.md), [sysctl(8)](/sysctl/8.md)

## HISTORY

The **lmenv** driver first appeared in OpenBSD 3.9.

## AUTHORS

The **lmenv** driver was written by Mark Kettenis ⟨*kettenis@openbsd.org*⟩.