[Trlog] SBDVP - Arrrrrrrrg

[Kevin Schmidt]

Ron et al.,

As Pete mentioned, I am living in Trieste, Italy until the middle of
July when I return to Tempe, Arizona. My laptop runs linux (it did come
with Windows XP but I erased that), and can only run SBDVP and TR under
the linux DOS emulator. What's worse is that I don't have a radio
either.  The DOS emulated soundblaster under linux does not support
recording.  SBDVP functions fine in this system but, of course, will
only play files not record.

SBDVP uses the sound blaster pro subset of sound blaster commands. The
sound blaster pro only used one DMA so SBDVP only activates one.
Nearly all sound cards emulate the sound blaster pro, and that is why
SBDVP works for most of them.  Most modern sound cards use 2 DMAs so
that recording and play back can happen simultaneously.  SBDVP should
work with soundcards with 2 DMAs, it just uses the same one for recording
and play back.

When I cobbled together SBDVP I assumed that Tree would move away from
DOS to a real operating system where sound card manipulations are very
easy. We all have better things to do than worry about DMAs etc.  That
is what the operating system is supposed to do. I never thought the
SBDVP would still be in use after this much time.

If anyone wants to experiment, the source code to SBDVP is included in
the distribution. It is compiled with Borland Turbo C, and this DOS C
compiler is so old, that it is now in the Borland Developer Network
"Museum" and anyone who wishes can download it from them, free of
charge at, <http://bdn.borland.com/museum/>. The Makefile provided in
the distribution shows the compiler flags needed. I apologize for the
ugliness of the source to SBDVP.

73 Kevin w9cf

> From: Ronald Rossi <rrossi at btv.ibm.com>
> 
> 
> I have been doing a little bit of research and found reference to the
> sample rate being set differently between SB16 and other cards. The rate
> in SBDVP is set using a timeconstant related to the sample rate in Hz.
> The SB16 is set using the sample rate. Is is possible this may be partly
> to blame? It also appears that the rate is set independently for play
> and record. I could not see where this was covered in the SBDVP source.
> 
> Pete or Don, Maybe you could check to see what the sample rate of the
> recorded file is when you play it with GoldWave or whatever.
> 
> -- 
> 73 es God Bless de KK1L...ron (kk1l at arrl.net) <><
> QTH: Jericho, Vermont
> My page: http://www.qsl.net/kk1l
=-------------------------------------------------------------
Kevin Schmidt, w9cf at ptolemy.la.asu.edu, http://fermi.la.asu.edu/w9cf
Department of Physics and Astronomy
Arizona State University, Tempe, AZ 85287-1504
(480) 965-8240 Fax: (480) 965-7954