DATAORG is a macro that is #define’d near the top of the BIOS. It can be adjusted up or down in
0x1000 byte increments. With separate I&D, adjusting it up gives more space for root constants and less
for root variables. Without separate I&D, adjusting it up gives more space for root code and constants and
less space for root variables.
In DC10 and above the DATAORG macro has been replaced by ROOT_SIZE_4K