Datasheet

13. DSU - Device Service Unit...................................................................................... 71
13.1. Overview.................................................................................................................................... 71
13.2. Features..................................................................................................................................... 71
13.3. Block Diagram............................................................................................................................ 72
13.4. Signal Description...................................................................................................................... 72
13.5. Product Dependencies............................................................................................................... 72
13.6. Debug Operation........................................................................................................................73
13.7. Chip Erase..................................................................................................................................75
13.8. Programming..............................................................................................................................76
13.9. Intellectual Property Protection.................................................................................................. 76
13.10. Device Identification...................................................................................................................78
13.11. Functional Description................................................................................................................79
13.12. Register Summary..................................................................................................................... 84
13.13. Register Description...................................................................................................................86
14. Clock System.........................................................................................................109
14.1. Clock Distribution..................................................................................................................... 109
14.2. Synchronous and Asynchronous Clocks.................................................................................. 110
14.3. Register Synchronization..........................................................................................................110
14.4. Enabling a Peripheral............................................................................................................... 115
14.5. Disabling a Peripheral.............................................................................................................. 115
14.6. On-demand, Clock Requests................................................................................................... 115
14.7. Power Consumption vs. Speed................................................................................................ 116
14.8. Clocks after Reset.................................................................................................................... 116
15. GCLK - Generic Clock Controller...........................................................................117
15.1. Overview...................................................................................................................................117
15.2. Features................................................................................................................................... 117
15.3. Block Diagram.......................................................................................................................... 117
15.4. Signal Description.....................................................................................................................118
15.5. Product Dependencies............................................................................................................. 118
15.6. Functional Description.............................................................................................................. 119
15.7. Register Summary....................................................................................................................125
15.8. Register Description................................................................................................................. 125
16. PM – Power Manager............................................................................................139
16.1. Overview.................................................................................................................................. 139
16.2. Features................................................................................................................................... 139
16.3. Block Diagram.......................................................................................................................... 140
16.4. Signal Description.................................................................................................................... 140
16.5. Product Dependencies.............................................................................................................140
16.6. Functional Description..............................................................................................................142
16.7. Register Summary....................................................................................................................150
16.8. Register Description................................................................................................................. 150
17. SYSCTRL – System Controller............................................................................. 172
17.1. Overview.................................................................................................................................. 172
SAM D21 Family
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40001882D-page 4