Audio Card
1 message · 2004-07-24 → 2004-07-24 · Yahoo Group era · View archive on archive.org
Participants: Jeff
Preserved from the Timex/Sinclair 2068 Yahoo Group (2001–2019), which is no longer online. Text reproduced from the archive.org archive; email addresses masked.
Messages
1. Audio Card
Jeff · Sat, 24 Jul 2004 16:51
Alvin;
What did you have in mind for the D/A and A/D card? If it is for
audio record and playback, there are several codecs that would do the
trick (look on Digikey's web site for a good selection). The problem
is that the best ones are 16 bits rather than 8. One could simply
throw away the lower 8 bits, though.
If you are looking for a more general purpose card then we probably
should use general purpose A/D and D/A devices - SARs and R2R
respectively.
I am a little concerned about throughput for the board. At 44KS/s
you for streaming audio we are spooling a great deal of data onto and
off of the hard drive which will probably pretty much monopolize the
system bandwidth. The FPGA DMA engine and any reasonable hard disk
or CF/SmartMedia should be able to support this for reading. Writing
may be a bit more problematic.
I'd like your ideas about how the audio interface would be used and
how this should work. If we make this a separate card, it should
probably have its own mass storage so that it doesn't tie up the
system bus.