circuitpython/ports/nrf/supervisor
jepler f38ee42874 nrf: Add i2s audio output
Testing performed: I used a Particle Xenon with a HDA1334 I2S DAC.
I played a variety of mono 16-bit samples at 11025 and 22050Hz nominal
bit rates.  With this setup, all the 11025Hz samples sound good.
I tested play, pause,  and loop functionality.

During some runs with 22050Hz samples, there were glitches.  However,
these may have only occurred during runs where I had set breakpoints
and watchpoints in gdb.

I also tested with a MAX98357A I2S amplifier.  On this device, everything
sounded "scratchy".  I was powering it from 5V and the 5V rail seemed
steady, so I don't have an explanation for this.  However, I haven't
tried it with a SAMD board.
2019-09-08 16:46:35 -05:00
..
cpu.s Support gathering register values on nrf. 2018-07-03 06:31:07 -07:00
internal_flash.c Fix crash in internal filesystem on nrf 2019-05-08 15:43:18 -07:00
internal_flash.h Fixups for adafruit/circuitpython#1042 2019-04-16 14:53:44 +10:00
internal_flash_root_pointers.h Move atmel-samd to tinyusb and support nRF flash. 2018-11-08 17:25:30 -08:00
port.c nrf: Add i2s audio output 2019-09-08 16:46:35 -05:00
qspi_flash.c Don't let a background task call run_background_tasks() 2019-04-09 20:23:01 -04:00
serial.c Move atmel-samd to tinyusb and support nRF flash. 2018-11-08 17:25:30 -08:00
usb.c refactor nrfx from supervisor/usb.c 2019-01-30 22:30:23 +07:00