MOS

Mute OS

Memory Structure

know memory structure is important for system,which memory can be allocated,which can't.this is a job of system.

+----------+ <-0X FFFF FFFC
|up to 4GB |
|	       |
\/\/\/\/\/\/

/\/\/\/\/\/\
|          |
|extend RAM|
+----------+ <-0X 0010 0000
+----------+ <-0X 000F FFFC
|BIOS   ROM|
+----------+ <-0X 000F 0000
+----------+ <-0X 000E FFFC
|16 bits   |
|devices,  |
|expansion |
|ROMs      |
+----------+ <-0X 000C 0000
+----------+ <-0X 000B FFFC
|   VGA    |
|  Display |
+----------+ <-0X 000A 0000
+----------+ <-0X 0009 FFFC
|    LOW   |
|  Memory  |
+----------+ <-0X 0000 0000
|<-4bytes->| HEAD Address of 4 bytes(32 bits)

physical address = 16 * segment + offset