39.6.2.1 Initialization

To operate the TRNG, do the following:
  • Configure the clock source for CLK_TRNG_APB in the Main Clock Controller (MCLK) and enable the clock by writing a ‘1’ to the TRNG bit in the APB Mask register of the MCLK.
  • Optional: Enable the output event by writing a ‘1’ to the EVCTRL.DATARDYEO bit.
  • Optional: Enable the TRNG to Run in Standby sleep mode by writing a ‘1’ to CTRLA.RUNSTDBY.
  • Enable the TRNG operation by writing a ‘1’ to CTRLA.ENABLE.

The following register is enable-protected, meaning that it can only be written when the TRNG is disabled (CTRLA.ENABLE is zero):

  • Event Control register (EVCTRL)

Enable-protection is denoted by the Enable-Protected property in the register description.