Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!wuarchive!uunet!mcsun!ukc!acorn!kwelton
From: kwelton@acorn.co.uk (Kevin Welton)
Newsgroups: comp.sys.acorn
Subject: Re: SCSI interfaces - background capability
Message-ID: <8079@acorn.co.uk>
Date: 27 Jun 91 12:32:53 GMT
References: <9106251106.AA05878@ucbvax.Berkeley.EDU>
Organization: Acorn Computers Limited, Cambridge, UK
Lines: 23

torq@tardis.computer-science.edinburgh.ac.uk writes:

>On the Acorn SCSI card that I have, there is a facility to do background
>transfer, by setting b29 of r1 and a address to call in r6 on entry to 
>SCSI_op. Is this facility unique to the acorn card? is it used in riscix?

The facility is nothing to do with Acorn's SCSI card, it is a feature
provided by RISC OS.  Under RISCiX, the kernel blocks all read/write
operations until the transfer is complete, but there is nothing stopping
you forking off another process to do the transfer for you.

>Which cards are actually compatible with the riscix device drivers? Since
>acorn have released riscix to ordinary archimedes owners it might be of some
>benefit to know this..

The RISCiX device drivers work with Acorn's SCSI card only.

>Andy
Kevin
-- 
Kevin Welton				Email: kwelton@acorn.co.uk
Acorn Computers Ltd			Phone: (+44) 223 245200
Cambridge, UK				Fax:   (+44) 223 210685