Subject: Re: snapper microphone support
To: None <port-macppc@netbsd.org>
From: Magnus Henoch <mange@freemail.hu>
List: port-macppc
Date: 12/20/2005 17:45:15
Michael <macallan18@earthlink.net> writes:
> Sorry, didn't get around to play with it yet. Do you have the data sheet
> or did you get everything you know about the chip from snapper* ? ( the
> data sheet is available from ti.com or I could just mail it to you ).

I have it; I found it at the URL in the source file.

> I'm not at all sure snapper_write_mixer() does The Right Thing(tm) in
> all cases ( most likely my fault - the regs[5] = ... line should
> probably be regs[6] = ... )

Yes, it seems it should.  And maybe it should have greater range;
putting 0x10 00 00 in the register gives 0 dB, but the current code
never reaches that value.

I tried playing with that, using the mixer value as the entire first
byte.  (That's probably too much; when setting it to 128 I just get
feedback.)  With certain combinations of microphone and playback
volumes I can hear my own voice quite well.

Magnus