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From: awang@isl.Stanford.EDU (Avery Wang)
Newsgroups: comp.sys.next
Subject: fast_dma_support.asm DSP question
Message-ID: <1991Jun19.235758.25919@EE.Stanford.EDU>
Date: 19 Jun 91 23:57:58 GMT
Sender: usenet@EE.Stanford.EDU (Usenet)
Organization: Stanford University
Lines: 22

I noticed that in the dsp_dma_stream example in the 2.0 release, in  
the file dsp_dma_stream.asm there is the conditional compile:
;
; input/output routines, DMA and non-DMA i/o
;
        if DOUBLE_BUFFER
          include 'fast_dma_support.asm'
        else
          include 'simple_dma_support.asm'
        endif

In the example simple_dma_support.asm is included.  I am very  
interested in using the fast_dma_support.asm file if it exists.
the simple_dma_support results in i/o blocking which can potentially  
waste a lot of 56001 cycles that could be better used computing  
something.  fast_dma_support is supposedly similar to what the Music  
Kit uses and features double-buffering and interrupt-driven DMA.   
Does anyone know if this file even exists, and if so, where I can get  
a copy?

Thanks,
-Avery Wang