[comp.sys.sun] 386i interrupt performance under DOS window

fkuhl@amadeus.mitre.org (F. S. Kuhl) (01/11/89)

I am attempting to interface a Dialogics Dialog/20 digital audio card to a
386i, and am encountering some problems with interrupt performance under a
DOS window.  This card is a memory-mapped speech card which generates
audio from ADPCM data shipped to it from a terminate-and-stay-resident
driver supplied with the card.  In order for the card to operate properly,
the driver must supply the card with speech data approximately eight times
per second.  When the system is quiescent, the DOS emulator has no trouble
providing the driver with enough time to accomodate the needs of the
board.  When other processes are active, however, Sunview screen updates
effectively stall the driver, as do periods of extremely heavy CPU usage.
Light-to-moderate CPU usage without screen updates seem to pose no
problems with the performance of the board's driver.  Does anybody know of
a way to boost the DOS window's responsiveness to interrupts so that it
will continue to have enough time to adequately service the board when
other processes are active?  We have already attempted running the DOS
window with a "nice" value of -5 to no avail.

	--Fred Kuhl, fkuhl@amadeus.mitre.org