Asdcarl.120
net.periphs
utzoo!decvax!ucbvax!ucsfcgl!sdcarl!rusty
Thu Dec 10 21:13:32 1981
hardware glitch
This seems a bit obscure to us, maybe someone out there can
shed some light.

We have a set of Digital Sound Corp. digital to analog and
analog to digital converters on our Vax 11/780. We typically
run our converters at a 50kHz sampling rate, we are doing
computer music. The way the driver is set up it does dma into
or out of a buffer in user space. The problem is that if the
buffer isn't page aligned we get clicks in the sound, 1 click
per buffer (it uses buffer chaining with 2 buffers, the 2
buffers are reused circularly). Our solution is to use valloc
to get the buffers properly aligned.

Any ideas about the clicking?