29.2.1.5 Row Contents

Each physical row initially stores the contents of one or two logical RWW EEPROM memory pages (it depends on application configuration file). This quarters or halves the available storage space for the emulated RWW EEPROM but reduces the overall number of row erases that are required, by reserving two or three pages within each row for updated versions of the logical page contents. See Figure 29-2 for a visual layout of the RWW EEPROM Emulator physical memory.

As logical pages within a physical row are updated, the new data is filled into the remaining unused pages in the row. Once the entire row is full, a new write request will copy the logical page not being written to in the current row to the spare row with the new (updated) logical page data, before the old row is erased.

When it is configured, each physical row stores the contents of one logical RWW EEPROM memory page. This system will allow for the same logical page to be updated up to four times into the physical memory before a row erasure procedure is needed. In the case of multiple versions of the same logical RWW EEPROM page being stored in the same physical row, the right-most (highest physical memory page address) version is considered to be the most current.