MEM F000h:C000h - Tandy ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware.  The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly. ID BYTE
Size:	BYTE
Note:	If the BYTE at this location is equal to 21h, some Microsoft software
	  assumes this is a Tandy machine, and for example trusts the bits 1-0
	  at 0040h:00B5h.
SeeAlso: MEM 0040h:00B5h"Tandy",INT 15/AH=C0h