1.\" 2.\" Copyright (c) 1994 James A. Jegers 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. The name of the author may not be used to endorse or promote products 11.\" derived from this software without specific prior written permission 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23.\" 24.Dd November 29, 1994 25.Dt AHA 4 i386 26.Os NetBSD 27.Sh NAME 28.Nm aha 29.Nd Adaptec 154x SCSI adapter driver 30.Sh SYNOPSIS 31.Cd "aha0 at isa? port 0x330 irq ? drq ?" 32.Cd "scsibus* at aha?" 33.Sh DESCRIPTION 34The 35.Nm aha 36driver provides support for the following SCSI adapters: 37.Pp 38.Bl -tag -width -offset indent -compact 39.It Adaptec AHA-154xA 40.It Adaptec AHA-154xB 41.It Adaptec AHA-154xC 42.It Adaptec AHA-154xCF 43.It Buslogic BT-54x 44.El 45.Sh BUGS 46The 47.Nm 48driver can not be used on systems with more than 16 megabytes of 49memory. 50.Pp 51Due to the 24 bit addressing limitation of the ISA bus, The SCSI 52adapter's onboard DMA controller is unable to access memory with 53addresses greater than 16 megabytes. 54.Pp 55This restriction can be fixed with "bounce buffers", buffers in low 56memory which are used whenever data to be transfered to or from the 57SCSI adapter is above the 16 megabyte threshold. The data is copied 58to the bounce buffer, then copied from the bounce buffer to its 59destination. 60.Sh SEE ALSO 61.Xr intro 4 , 62.Xr sd 4 , 63.Xr st 4 , 64.Xr cd 4 , 65.Xr ch 4 66