I2S driver for STM32F4#621

Draft

ledneczki wants to merge 6 commits intomodm-io:developfrom

ledneczki:feature/i2s-stm32f407

Commits on Apr 18, 2021

[I2S] Setup PLL for the I2S peripheral
ledneczki
committed

Commits on Apr 21, 2021

[I2S] Setup basic I2S driver template package
ledneczki
committed

Commits on Apr 22, 2021

[I2S] Add pin configuration for I2S DAC
ledneczki
committed

Commits on Apr 28, 2021

[I2S] Add first draft of I2S master configuration
ledneczki
committed

Commits on May 4, 2021

[I2S] Add audio DAC driver and interrupt driven I2S
ledneczki
committed

Commits on May 9, 2021

[I2S] Fix audio DAC driver
ledneczki
committed