hi,

here we come to parallel FRAM. It is faster than EEPROM - full cycle time is about 130ns for FM1808. In theory it gives max. OSC frequency for about 45MHz for standard MCU51 (6 cycles for /RD,/WR). As for faster MCU so the stretch feature may be used.
Moreover, FRAM supports much more write cycles than EEPROM.

Hmm, it seems the original poster has no interested with the thread anymore.

Regards,
Oleg