ST M34C02 handbook

The M34C02 is a 2 Kbit serial EEPROM memory able to lock permanently the data in its first half (from location 00h to 7Fh). This facility has been designed specifically for use in DRAM DIMMs (dual interline memory modules) with Serial Presence Detect. All the information concerning the DRAM module configuration (such as its access speed, its size, its organization) can be kept write protected in the first half of the memory. This bottom half of the memory area can be write-protected using a specially designed software write protection mechanism.

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