SLUUDG7 December 2025 MSPM33C321A
The GSC utilizes both the MPU and SAU to configure memory with security and privilege attributes. To configure this the GSC has three separate controllers: Peripheral Protection Controller (PPC), SRAM Protection Controller (SPC), and Flash Protection Controller (FPC). For details on how to configure and use the registers please see the MSPM33C3-Series 160MHz Microcontrollers Technical Reference Manual
The GSC has similar properties to the SAU and MPU. This can lead confusion on which peripheral should be used for protecting memory. The SAU and MPU are limited on how many regions can configured or address granularity. For example the SAU for M33 devices can only attribute 8 regions of memory with the non-secure and secure attribute. Unconfigured regions of memory are left with the secure attribute. The GSC however attributes regions in a 2kB size allowing 255 different regions of security on a 1 MB device. Each one of these 2kB regions can be attributed either secure or privilege access.