15.7.1 Control A
| Name: | CTRLA |
| Offset: | 0x00 |
| Reset: | 0x00 |
| Property: | PAC Write-Protection, Write-Synchronized bit(s) |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| SWRST | |||||||||
| Access | R/W | ||||||||
| Reset | 0 |
Bit 0 – SWRST Software Reset
Writing a zero to this bit has no effect.
Setting this bit to 1 will reset all registers in the GCLK to their initial state after a Power Reset, except for generic clocks and associated Generators that have their WRTLOCK bit in PCHCTRLm set to 1.
Refer to GENCTRL Reset Value for details on GENCTRLn register reset.
Refer to PCHCTRL Reset Value for details on PCHCTRLm register reset.
Due to synchronization, there is a waiting period between setting CTRLA.SWRST and a completed Reset. CTRLA.SWRST and SYNCBUSY.SWRST will both be cleared when the reset is complete.
Note:
- 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 or bits without SWRST are disallowed until the SYNCBUSY.SWRST bit is cleared by hardware.
| Value | Description |
|---|---|
| 0 | There is no Reset operation ongoing. |
| 1 | A Reset operation is ongoing. |