27.5.8.3 Data Structures
The SmartEEPROM algorithm relies on two virtual sectors (SEES) physically located in the last blocks of:
- BANKB if STATUS.AFIRST=1
- BANKA if STATUS.AFIRST=0
Only one SEES is active at a time, the other must be erased, ready for data reallocation.
The current active SEES is indicated in SEESTAT.ASEES:
- 0: SEES0 is active
- 1: SEES1 is active
SEESTAT.ASEES is loaded after Reset from a special fuse in the NVM which can be programmed or erased individually. This fuse can be set by issuing the ASEES1 command or cleared by issuing the ASEES0 command. SEESTAT.ASEES reflects this change immediately.
The maximum number of virtual pages is limited to 128.
A page allocation consists of assigning a SEEP to a virtual page for the first time. A page reallocation consists of assigning a new SEEP to an already existing virtual page. In both cases the selected virtual page index and the next available page are written.
The SEEP size (PSZ) is configurable. The number of blocks allocated per SEES is configurable.