外设 API
***************

.. toctree::
   :maxdepth: 2

   DAC <dac>
   I2C <i2c>
   PWM <pwm>
   RNG <rng>
   RTC <rtc>
   SPI <spi>
   UART <uart>
   TIMER <timer>
   WDG <wdg>
   GPIO <gpio>
   ADC <adc>