SUNAGAWA Keiki wrote:
> Colin Wood <cwood@ichips.intel.com> wrote:
> 
> Colin> Now for the survey part.  I'm including a copy of the
> Colin> source for my beeping program below.  I guess that
> Colin> it's really a square-wave tone generator.  Once
> Colin> you've compiled it (assuming "gcc -o beep beep.c"),
> Colin> you invoke it like so:
> 
> The code I sent drove ASC in free-wave mode and This drives
> it in four voice mode. 

No, this is the EASC's square-wave mode (which appears to simply be a
variation on synthesized/free-wave mode).  Four-voice or wavetable mode is
_much_ more complicated on both, mainly because the hand-coded assembly
does strange things to avoid running out of registers :-)

The ASC appears to have a dedicated square-wave mode.  The interesting
thing about it is that the current asc.c driver appears to be playing a
synthesized sound in the ASC's dedicated square-wave mode (i.e. it sets
0x830-0x837 to a value related to the frequency instead of to 0xFE like in
synthesized sound mode).

> It's pretty good that if there are
> some ioctls to handle both modes of [E]ASC.

I'm glad it works :-)  True synthesized sound might require more work,
tho.  I still haven't gotten it to stop coughing on the sample with
the 22kHz sampling rate, and that's what most are.  I may have an idea for
a workaround, tho.

> I think...
> 
> /dev/bell for bell device.

Some NetBSD platforms do have some minor device number versions of
/dev/audio used as a console bell, I think.  That might not be too hard to
do.

> /dev/audio for play audio file.
>
> Thoughts?

Definitely :-)  There is already a machine-independent /dev/audio.  All it
will take is writing the glue code once we've figured out exactly how the
silly thing works (or so I think ;-)

> Colin> 	temp = 0x11999999 / count;
> 
> The magic number is 0x58000000 on IIcx.  There may be
> another?

Possibly.  I didn't try it on my SE/30 last night because it was getting
late.  I assume that it will work on the original II-series Macs since the
sound hardware is pretty much the same as in my IIci.  I've got a dump of
the SE/30's .Sound driver.  I'll have to take a look at it to make sure
I'm not screwing anything up....
 
> BTW, I made a test prog. try to figure the 4 tones and it
> made a kind of harmony, but I found that I needed to
> implement the scheme to handle musical score even if there
> are limited only 4...

:-)  Cool.

Good luck!

-- 
Colin Wood                                 cwood@ichips.intel.com
Component Design Engineer - PMD                 Intel Corporation
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I speak only on my own behalf, not for my employer.