title: Is address 0xFFFFFFF0 hardwired for system BIOS ROM?
body: <p>I read this from a previous stack overflow answer: </p>
  
  <p>At initial power on, the BIOS is executed directly from ROM. The ROM chip is mapped to a fixed location in the processor's memory space (this is typically a feature of the chipset). When the x86 processor comes out of reset, it immediately begins executing from 0xFFFFFFF0.</p>
  
  <p>Follow up questions,</p>
  
  <p>Is this address 0xFFFFFFF0 hardwired just to access the system BIOS ROM and later after the system is up and running this address 0xFFFFFFF0 can not be used by RAM?</p>
  
  <p>Also, when this address 0xFFFFFFF0 is being us to access the system BIOS ROM, is the CPU accessing it as an IO device or Memory device?</p>