PNP(4)							 BSD/i386 Kernel Interfaces Manual						    PNP(4)

NAME

     pnp -- support for ``Plug and Play'' (PnP) ISA devices

DESCRIPTION

     The pnp driver enumerates ISA devices which support ``Plug and Play ISA Specification'' in the system.  It assigns ISA bus resources (inter-
     rupt line, DMA channel, I/O ports, and memory region) to each device and activates it.

     If it cannot assign necessary resources to a PnP ISA device without causing conflict with other devices in the system, the device will not be
     activated and will be unavailable to programs.

CAVEATS

     It is not possible to disable individual PnP ISA devices.	The pnp driver will find all devices conforming the PnP ISA specification and try
     to activate them all.

     There is no way to explicitly assign particular resource to the PnP ISA device.  The resource assignment is fully automatic and there is no
     provision for manual override.

SEE ALSO

     pnpbios(4)

STANDARDS

     Intel and Microsoft, Plug and Play ISA Specification, Version 1.0a, May 5, 1994.

     Clarifications to the Plug and Play ISA Specification, Version 1.0a, December 10, 1994.

HISTORY

     The pnp driver first appeared in FreeBSD 2.2.5.  It has been substantially updated in subsequent versions.

AUTHORS

     PnP support was originally written for FreeBSD 2.2.5 by Luigi Rizzo, based on initial work done by Sujal Patel.

BSD
								September 20, 2001							       BSD