---
name: "tcpcib"
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/tcpcib"
---

# tcpcib(4)

Intel Atom E600 series LPC bridge, timecounter and watchdog timer

## NAME

**tcpcib** – Intel Atom E600 series LPC bridge, timecounter and watchdog timer

## SYNOPSIS

**tcpcib\* at pci?** **isa\* at tcpcib?**

## DESCRIPTION

The **tcpcib** driver provides support for the Intel Atom E600 series LPC bridge and implements a 64-bit 14.3 MHz timecounter using the HPET timer.

The **tcpcib** driver also provides the standard [watchdog(4)](/watchdog/4.md) interface to the watchdog timer and may be used with [watchdogd(8)](/watchdogd/8.md). The watchdog timer can be configured via [sysctl(8)](/sysctl/8.md).

Once the watchdog timer resets the CPU, the driver reports it on the next boot displaying the “reboot on timeout” message in the [dmesg(8)](/dmesg/8.md).

The maximum timeout value supported by the watchdog timer is 600 seconds.

## SEE ALSO

[intro(4)](/intro/4.md), [isa(4)](/isa/4.md), [pci(4)](/pci/4.md), [watchdog(4)](/watchdog/4.md), [sysctl(8)](/sysctl/8.md), [watchdogd(8)](/watchdogd/8.md)

## HISTORY

The **tcpcib** driver first appeared in OpenBSD 5.2.

## AUTHORS

The **tcpcib** driver was written by Matt Dainty ⟨*matt@bodgit-n-scarper.com*⟩.

## BUGS

Apart from the core [pcib(4)](/pcib/4.md) functionality, timecounter and the [watchdog(4)](/watchdog/4.md) interface, the driver doesn't support any other aspects of the hardware.