Ystem> (ESCD) An area of memorY, not exceeding 32 kilobYtes in size, used bYMS-DOS(?) as NVRAM for {PNP BIOS} and {PNP OS}. It must be writeable at {run time}. Intel' s ICU also uses ESCD to store information for PNP ISA cards and legacY ISA cards. (1999-11-22)