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From: mac@uvacs.UUCP
Newsgroups: comp.arch
Subject: Re: Using a DMA chip in strange ways
Message-ID: <1257@uvacs.CS.VIRGINIA.EDU>
Date: Mon, 23-Feb-87 15:09:32 EST
Article-I.D.: uvacs.1257
Posted: Mon Feb 23 15:09:32 1987
Date-Received: Fri, 27-Feb-87 01:13:04 EST
References: <4343@columbia.UUCP>
Organization: U.Va. CS Department, Charlottesville, VA
Lines: 8
Summary: DMA for memory moves

>     Since the DMA chip on your favorite disk/tape controller works by stealing
> bus cycles when the CPU is busy with other things (like arithmetic), would
> there be any advantage in having a DMA chip which would simply be used for
> memory to memory copies (from user to kernel space, or from one user space to
> another)?

Been done.  I believe it was on the Univac 1100s.  Used for plated-wire to
core memory transfers, among other things.