Memory Map

Memory map

address	size	usage	description
0x00000	1024 Byte	unusable	interupt vector table
0x01000	4096 Byte	unusable	system.sys gets loaded here. It provides all the system calls and should therefor not be overriden.
0x02000	8 KiByte	unusable	directory cache. A copy of the current working directory gets loaded here for quick access. Gets overriden everytime a the directory is changed.
0x04000	8 KiByte	unusable	The file allocation table of the current drive gets loaded here. Is required to allow for file and directories to be read.
0x06000	1 Byte	read only	This byte represents the current color attribute. Can be used to print to the terminal in system color.
0x06001	1 Byte	reserved	Was used for settings. Might be used for kernel functions in the future.
0x06002	2 Byte	read only	This word contains the return code of the last execution.
0x06004	2 Byte	read only	This word saves the current length of the path.
0x06006	1 KiByte	read only	The current path is saved here.
0x06406	7164 Byte	unusable	This is the kernel stack.
0x08000	4 KiByte	read only	strings.sys gets loaded here to allow for language specific error messages etc. Can be accessed by language.asm.
0x09000	476 KiByte	free for use	A user programm gets loaded at address 0x09000. The programm has then guaranteed access to the space from 0x9000 up to 0x80000 without destroying the kernel.
0x80000	4 KiByte	unusable	The kernel keeps a copy of command.bin for quick access here.
0xB8000	4 KByte	special usage	Represents the videobuffer for text mode. Everything written to this area is displayed on the screen. The format is: [ even byte | odd byte ] [ ascii char | color attr. ]
0xB8FA0	???	undefined	Could be available for use. But BIOSes might put CMOS data or mappings here. If A20 Gate is enabled, this could range up to 0xFFFFF. Probe and use at your own risk.