Int 14 Fn 18  - Fossil - Read Block                                        [S]

   AH = 18h
   CX = maximum number of characters to transfer
   DX = port number
   ES:DI -> user buffer

Return: AX = number of characters transferred

See Also: AH=19h"FOSSIL",AH=83h"COURIERS",AX=FF02h,INT 6B/AX=0100h