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

# nvram(4)

driver for reading PC NVRAM contents

## NAME

**nvram** – driver for reading PC NVRAM contents

## SYNOPSIS

**pseudo-device nvram 1**

## DESCRIPTION

The **nvram** device provides read-only access to the non-volatile memory contained in the MC146818 real-time clock.

This data is provided as a seekable character device, */dev/nvram*. Checksums of the NVRAM contents are calculated over bytes 2 to 31 and stored in byte 32. A valid checksum is required for the driver to initialize.

## FILES

- */dev/nvram*

  ## HISTORY

**nvram** support was originally included in OpenBSD 3.7.