SLAU962A December 2025 – June 2026 MSPM33C321A , MSPM33C321A-Q1
There are three main power domains on MSPM33Cx devices:
The PD1 domain supports higher clock speeds for performance, and is disabled in certain operating modes to minimize power consumption. The PD0 domain supports ultra-low-power performance and is always enabled in operating modes in which the core regulator is operating.
There are four main data buses on MSPM33Cx devices:
The CPU and the DMA controllers are the bus initators in the device. Arbitration between the CPU and the DMAs for shared peripherals happens between the PD1 amd PD0 peripheral bus. The DMA does not have access to peripherals on the CPU-only PD1 peripheral bus or the CPU sub-system. As such, the CPU can access peripherals on the CPU-only PD1 peripheral bus at the same time that the DMA is processing a transaction on the PD1 or PD0 bus.
Likewise, the CPU can access SRAM or flash memory through the AHB bus matrix at the same time that the DMA is processing a transaction, so long as the DMA is not accessing the same memory that the CPU is attempting to access. Arbitration between the CPU and the DMA for memory systems (SRAM or flash memory) happens at the memory interface itself. All arbitration between the CPU and DMA is done on a round-robin basis.