INT 15 - Tandon memory mapper - Tandon MAPPER HARDWARE INITIALISATION CHECK ???
AX = F200h
CX = 454Dh
Return: CF clear if hardware already initialised
BX = upper RAM areas in use
bit 0: C000-C3FF
bit 1: C400-C7FF
...
bit 11: EC00-EFFF
CF set if hardware not initialised yet


15F200CX454D - Tandon memory mapper - Tandon MAPPER HARDWARE INITIALISATION CHECK ???