On Tue, 11 Jan 2000, Toru Nishimura wrote:

> As you might already know, ULTRIX does not use IOASIC DMA channel to
> handle Serial Desktop Bus data.  According to ULTRIX include files,

  No, I didn't know that.  Perhaps DEC was unable to make it work?

> DMA/non-DMA is #ifdef conditionalized, and kernel has no DMA
> code. ULTRIX manipulates Serial Desktop Bus data using complicated
> timeout()/untimeout() sequences in which I have not figured out the
> details.

  I guess what is needed is new interrupt processing that can leave
the Desktop Bus interrupts enabled as much as possible.

--
Michael L. Hitch			mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA