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Re: Ideas about an analog-to-digital converter API

Ken Hornstein wrote:
Actually, audio has a way to set the analog input range: it has input
gain control (multichannel, yet) as part of the mixer interface.

Hm, I looked at that, but I don't quite see how it's flexible enough.  For
example, the MAX197 (the A/D chip that is of interest to me) can be set
to go from 0 to 5V, 0 to 10V, -5 to 5V, or -10 to 10V.  The "gain" knob on
the mixer is an unsigned char.  I could set some "magic" gain values to
make that work, but it just feels ... wrong.  And there's not a good way
to query capabilies using that interface, from what I can see.

A hardware driver using MI audio can provide its own ioctls, you could use that for your driver (or layer another API between MI audio and your driver using custom ioctls).


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