---
name: "ssio"
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/ssio"
---

# ssio(4)

National Semiconductor PC87560 Legacy IO

## NAME

**ssio** – National Semiconductor PC87560 Legacy IO

## SYNOPSIS

**ssio\* at pci?**

## DESCRIPTION

The **ssio** driver provides support for the National Semiconductor PC87560 Legacy IO chip on systems with PA-8500 and later 64-bit CPUs. It configures the Programmable Interrupt Controllers integrated on the chip to route interrupts for the integrated [ohci(4)](/ohci/4.md) USB controller (which appears as a separate PCI device).

OpenBSD provides support for the following devices:

- [com(4)](/com/4.md)

  serial communications interface

- [lpt(4)](/lpt/4.md)

  parallel port driver

## SEE ALSO

[intro(4)](/intro/4.md), [pci(4)](/pci/4.md)

## HISTORY

The **ssio** driver first appeared in OpenBSD 4.2.