) Values EMM386 I/O dispatch function is called with: CX = Ring0 code selector for I/O handler's segment DS = Ring0 data selector for I/O handler's segment (alias of CS) EDX = faulting I/O address ECX = direction (00000008h for byte output, 00000000h for byte input) (reportedly 00h for byte/word input, 04h for byte/word output under DOS 6.22 EMM386) EAX = data in/out Return: (via FAR RET) CF clear if I/O access successfully virtualized CF set if access not virtualized (default handler will be called to perform the I/O) BUG: 32-bit I/O on trapped ports hangs the DOS 6.22 EMM386 SeeAlso: #02815