---
name: "viawd"
section: "4"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/viawd"
---

# viawd(4)

device driver for VIA south bridge watchdog timer

## NAME

**viawd** – device driver for VIA south bridge watchdog timer

## SYNOPSIS

**device** **viawd**

In [loader.conf(5)](/loader.conf/5.md): **viawd\_load="YES"**

## DESCRIPTION

The **viawd** driver provides [watchdog(4)](/watchdog/4.md) support for the watchdog interrupt timer present on VIA south bridge chipset (VT8251, CX700, VX800, VX855, VX900).

The VIA south bridge have a built-in watchdog timer, which can be enabled and disabled by user's program and set between 1 to 1023 seconds.

The **viawd** driver when unloaded with running watchdog will reschedule the watchdog to 5 minutes.

## SEE ALSO

[watchdog(4)](/watchdog/4.md), [watchdog(8)](/watchdog/8.md), [watchdogd(8)](/watchdogd/8.md), [watchdog(9)](/watchdog/9.md)

## HISTORY

The **viawd** driver first appeared in FreeBSD 10.0.

## AUTHORS

The **viawd** driver and this manual page were written by Fabien Thomas ⟨*fabient@FreeBSD.org*⟩.