INT 65 U - EZRECV v1.0 - API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running.  Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes.
	AX = function
	    0000h ???
		Return: AX = ??? or FFFFh
	    0001h ???
		Return: AX = status (0000h or 0001h)
	    0002h ???
		Return: AX = status (0000h or 0001h)
	    0003h set ??? to 0001h
		Return: AX = 0000h
	    0004h ???
		Return: AX = ???
Return: BH = COM port being used
	BL = speed???
	CH = ???
	CL = ???
	DX = ???
	DS = ???
	ES = EZRECV data segment
Program: EZRECV is a background Zmodem file receiver by Express Consulting