Each master connected to the AHB multilayer is assigned a default natural priority.
| Bus master name | Natural relative priority | In/Out | Description |
|---|---|---|---|
| CPU | Highest priority | I/O | |
| RADIO | I/O | ||
| CCM/ECB/AAR | I/O | Same priority and mutually exclusive | |
| UARTE0/SPIM0/SPIS0/TWIM0/TWIS0 | Lowest priority | I/O | Same priority and mutually exclusive |