Memory Organization

Refer to the Physical Memory Map for memory sizes and addresses for each device.

The NVM is organized into rows, where each row contains four pages, as shown in the NVM Row Organization figure. The NVM has a row-erase granularity, while the write granularity is by page. In other words, a single row erase will erase all four pages in the row, while four write operations are used to write the complete row.

Figure 1. NVM Row Organization

The NVM block contains the NVM Rows which contain calibration and system configuration, the FLASH area intended to store code and a separate array dedicated to data storage called Data FLASH that can be modified while the FLASH is read (no bus stall). All these areas are memory mapped. Refer to the NVM Organization figure below for details.

The NVM Rows contain factory calibration and system configuration information. These spaces can be read from the AHB bus in the same way as the FLASH. Note that Data FLASH requires more cycles to be read. The Data FLASH are can be executable, however this is not recommended as it can weaken an application security and also affect performances.

Figure 2. NVM Memory Organization

The lower rows in the FLASH can be allocated as a boot loader section by using the BOOTPROT fuses.

The boot loader section size is defined by the BOOTPROT fuses expressed in number of rows.