[Arm-netbook] ZeroPhone

[Luke Kenneth Casson Leighton]

On Tue, Apr 18, 2017 at 10:17 AM, GaCuest <gacuest at gmail.com> wrote:

> Maybe it's easier 3 speakers, a basic speaker directly for the
> STM32F (when using only the STM32F) and two good
> speakers, connected to the CM108H, when you use the
> EOMA68 (in this case the speaker of the STM32F would not work).

 as a phone that would be... odd.

 but not totally unprecedented.  the HTC Universal had an insanely
ridiculous number of audio paths.  something like SEVEN separate
outputs and FIVE inputs - no wonder it needed not just the AK4641 but
also a separate TI audio multiplexer IC.

 because the screen was flippable there were two separate mics and
earpiece speakers, one each on each side.  then it had separate stereo
speakers built into the base.  then there was a headphone jack.  and a
car stereo mode (with a cable to plug in), *and* bluetooth.

 if the chosen EC were capable of handling I2S then it would be
reasonable to drop in something like an AK4641 or a really really
basic AC97 Audio IC, then use the USB connection between the EC and
EOMA68 to emulate USB-audio: job done.

 just doing some quick google searches "STM32F072 I2S" it appears that
some people have actually successfully done this - one person
(admittedly) with an STM32F4 not the F0.  on the chibios.com web site
someone even posted working demo code.

l.