Interrupt Mask Register
| MOSCXTS | Main Crystal Oscillator Status Interrupt Mask |
| LOCKA | PLLA Lock Interrupt Mask |
| MCKRDY | Master Clock Ready Interrupt Mask |
| PCKRDY0 | Programmable Clock Ready 0 Interrupt Mask |
| PCKRDY1 | Programmable Clock Ready 1 Interrupt Mask |
| MOSCSELS | Main Oscillator Selection Status Interrupt Mask |
| MOSCRCS | Main On-Chip RC Status Interrupt Mask |
| CFDEV | Clock Failure Detector Event Interrupt Mask |