---
name: "eso"
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/eso"
---

# eso(4)

ESS Technology Solo-1 PCI AudioDrive audio device

## NAME

**eso** – ESS Technology Solo-1 PCI AudioDrive audio device

## SYNOPSIS

**eso\* at pci?** **audio\* at eso?**

## DESCRIPTION

The **eso** device driver supports sound cards based on ESS Technology Solo-1 PCI AudioDrive chips (ES1938 and ES1946), e.g. the TerraTec 128i PCI card.

## DIAGNOSTICS

- eso0: can't map Audio 1 DMA into I/O space

  PCI autoconfiguration did not map the first audio channel DMA controller into I/O space at a suitable address, and the driver was not able map it by itself. In that case only playback functionality will be available.

- eso0: reset timeout

  The device failed to acknowledge being reset.

- eso0: RDR timeout

  The driver timed out reading data from a controller register.

- eso0: WDR timeout

  The driver timed out waiting to send a command or writing to a controller register.

## SEE ALSO

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

## HISTORY

The **eso** device driver appeared in OpenBSD 2.5.

## BUGS

The game port and MIDI port are not supported.