US/European BIOS screenshotThe last value written to is also saved in RAMlocation $c000 (the first byte of RAM). If no header isfound at any of the three locations, the slot is assumed to be empty.The next check is the region: if the high four bits of the last byte ofthe header do not equal 4, it is rejected with a 'SOFTWARE ERROR' message.Finally, it checks the checksum using this code. Itdoes this from offsets $7ff0, $3ff0 and $1ff0 in turn.It checks to see if the first eight bytes match the ASCII string' TMR SEGA' if so, it proceeds to further tests. For each slot, 16 bytes are copied toRAM and checked if they contain a valid.
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