51.6.2.1 Initialization

The following registers are enable-protected, meaning that they can only be written when the ADC is disabled (CTRLA.ENABLE = 0):

• The Control A register (CTRLA), except the ENABLE and SWRST bits
• The Event Control register (EVCTRL)
• The Calibration register (CALIB)

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