---
name: "ieee1284_ecp_fwd_to_rev"
section: "3"
platform: "linux"
package: "libieee1284"
version: "0.2.11-19"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ieee1284_ecp_fwd_to_rev"
---

# ieee1284\_ecp\_fwd\_to\_rev(3)

ECP direction switching

## NAME

ieee1284\_ecp\_fwd\_to\_rev, ieee1284\_ecp\_rev\_to\_fwd - ECP direction switching

## SYNOPSIS

**int ieee1284\_ecp\_fwd\_to\_rev(struct parport \****port***);**

**int ieee1284\_ecp\_rev\_to\_fwd(struct parport \****port***);**

## DESCRIPTION

These functions are used to switch directions when in ECP mode. On negotiation to ECP mode the direction is forward (in other words, host-to-peripheral). Use **ieee1284\_ecp\_fwd\_to\_rev** to switch from forward to reverse, and **ieee1284\_ecp\_rev\_to\_fwd** to switch from reverse to forward.

They act on the parallel port associated with *port*, which must be claimed.

## RETURN VALUE

**E1284\_OK**

Direction switched successfully.

**E1284\_NOTIMPL**

The *port* lacks the required capability. This could be due to a limitation of this version of libieee1284, or a hardware limitation.

**E1284\_INVALIDPORT**

The *port* parameter is invalid (for instance, perhaps the *port* is not claimed).

## AUTHOR

**Tim Waugh** \<twaugh@redhat.com\>

Author.

## COPYRIGHT

Copyright © 2001-2003 Tim Waugh\