SLAU962A December 2025 – June 2026 MSPM33C321A , MSPM33C321A-Q1
The MCLK/2 (Half Clock) domain is a synchronous clock domain derived from the main MCLK clock using a divider circuit. The MCLK/2 domain operates at MCLK divided by two, providing a reduced clock rate for serial peripheral communications and timer functions that do not require maximum bandwidth. Refer to the device specific datasheet for more information on which peripherals and functions operate in the MCLK/2 domain. The clock domain maintains synchronization with the MCLK domain through a common clock root with integrated divider logic.
The clock divider circuit provides clock delivery to the MCLK/2 domain. The divider allows selection between divide-by-2 operation or bypass mode through the MCLKCFG[26] configuration bit. The divider configuration options are as follows:
| MCLKCFG[26] | Divider Select |
|---|---|
| 0 | The divider is bypassed (By1), and the MCLK/2 domain receives the full MCLK clock frequency. |
| 1 | The divider is enabled (By2), and the MCLK/2 domain receives MCLK divided by 2. |
NOTE: When MCLKCFG[26] is programmed to 1 (By2 mode), this bit forces MCLKCFG[24] to 1. User writes to MCLKCFG[24] are ignored when MCLKCFG[26] = 1. This dependency maintains proper clock domain configuration and prevents conflicting register settings.
The MCLK/2 domain is active and configured when the device operates from the HSCLK. The domain is inactive and not used during the following scenarios: