From owner-freebsd-hardware Mon Apr 20 10:27:09 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id KAA17420 for freebsd-hardware-outgoing; Mon, 20 Apr 1998 10:27:09 -0700 (PDT) (envelope-from owner-freebsd-hardware@FreeBSD.ORG) Received: from ryouko.nas.nasa.gov (ryouko.nas.nasa.gov [129.99.34.103]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA17412 for ; Mon, 20 Apr 1998 17:27:04 GMT (envelope-from greg@ryouko.nas.nasa.gov) Received: from ryouko.nas.nasa.gov (localhost [127.0.0.1]) by ryouko.nas.nasa.gov (8.8.7/NAS8.8.7) with ESMTP id KAA01852; Mon, 20 Apr 1998 10:26:26 -0700 (PDT) Message-Id: <199804201726.KAA01852@ryouko.nas.nasa.gov> To: Karl Pielorz cc: freebsd-hardware@FreeBSD.ORG Subject: Re: Recomended ISA SCSI Cards In-reply-to: Your message of "Mon, 20 Apr 1998 17:44:58 BST." <353B7B8A.65E9B10C@tdx.co.uk> Date: Mon, 20 Apr 1998 10:26:26 -0700 From: "Gregory P. Smith" Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > Can anyone recomend any good ISA SCSI cards to use with FreeBSD? - > Preferably something that'll work with a machine with >16Mb of RAM etc. - I > have a 1542 but it's been nothing but trouble... ... > I'm not too sure I would want to replace an AHA1542 with an AHA1520/22 > though - unless anyone else has any comments? "good" and "ISA" should not be used in the same paragraph. Any "good" ISA SCSI card is busmastering. The ISA bus only has 24 address lines, meaning busmastering ISA cards can only access the first 16mb of RAM. Your other option is the port I/O style card such as the AHA1522. These require lots of CPU for the transfer but don't have the 16mb limit. My ISA recommendation is the 1542, followed by a 1522 if you don't like the 16mb thing (really, these are your only sane choices). Most OSes drivers will work around the 16mb limit (w/ a performance hit) and copy data in/out of the low 16mb for busmastering ISA. I don't, however, know the state of FreeBSD's aha1542 driver; they might not have implemented that. Real recommendation: get a PCI motherboard, they're cheap. Greg To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message