Question of Reset

When the system power up,the first instruction execute from flash. what is the start address of flash ? In the NS7502 Board ,I find it is 0x0a000000.How the syetem set the start address? I also read some book about ARM chip.The ARM chip’s start address is 0x0. Is there some special in NS7520?

In reset.s the PC is set to 0x0A000000 from 0x0