42.8.1 Control A
| Name: | CTRLA | 
| Offset: | 0x00 | 
| Reset: | 0x00 | 
| Property: | PAC Write-Protection, Write-Synchronized | 
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| ENABLE | SWRST | ||||||||
| Access | R/W | W | |||||||
| Reset | 0 | 0 | 
Bit 1 – ENABLE Enable
Due to synchronization, there is delay from updating the register until the peripheral is enabled/disabled. The value written to CTRL.ENABLE will read back immediately and the corresponding bit in the Synchronization Busy register (SYNCBUSY.ENABLE) will be set. SYNCBUSY.ENABLE is cleared when the peripheral is enabled/disabled.
| Value | Description | 
|---|---|
| 0 | The AC is disabled. | 
| 1 | The AC is enabled. Each comparator must also be enabled individually by the Enable bit in the Comparator Control register (COMPCTRLn.ENABLE). | 
Bit 0 – SWRST Software Reset
Writing a '0' to this bit has no effect.
Writing a '1' to this bit resets all registers in the AC to their initial state, and the AC will be disabled.
Writing a '1' to CTRLA.SWRST will always take precedence, meaning that all other writes in the same write-operation will be discarded.
- When the CTRLA.SWRST is written, the user must poll the SYNCBUSY.SWRST bit to know when the reset operation is complete.
 - During a SWRST, access to registers/bits without SWRST are disallowed until the SYNCBUSY.SWRST is cleared by hardware.
 
| Value | Description | 
|---|---|
| 0 | There is no reset operation ongoing. | 
| 1 | The reset operation is ongoing. | 
