I use the SmartEeprom of an ATSAMD51J20A µC. The current and working configuration has a total EEPROMsize of 1024 bytes (fuses: SEESBLK = 0x08 and SEEPSZ = 0x01). Now I need to increase the size up to 2048, but unfortunately this doesn't work.

If I set the fuses to SEESBLK = 0x10 and SEEPSZ = 0x01, the appropriate GUI in my IDE (microchip studio) writes 0x00 into SEEBLK!

After some trial and error, it seems to me that the upper 4 bits of SEESBLK are ignored by the fuse-programing tool of microchip studio. For example, if I want to program 0x16 to SEESBLK (I know invalid configuration) a 0x06 is programed to the SEEBLK fuse. If I want to program 0x12, it programs just 0x02.

I didn't find any limitations in the data sheet, the corresponding tables theoretically provides configurations with significantly more EEPROMsize and the µC has 1MB flash available.

Does anyone have experience with this and uses the SmartEEEPROM with the mentioned µC with a size of more than 1024 bytes?