COM-Port by Vertex

If you read furthur down the archive entry, you will see that Vertex's code isn't all correct.

"What is going on? The offsets for the DCB at offset 8 are bits not DWORDS."

Function openComport(comport, baudRate)

	Local dcbBaudRate, driverHandle, dcb
   
	If comport > 255 Or comport < 0 Then
		Return INVALID_HANDLE_VALUE
	EndIf
   
	Select baudRate
		Case 110
			dcbBaudRate = CBR_110
		Case 300
			dcbBaudRate = CBR_300
		Case 600
			dcbBaudRate = CBR_600
		Case 1200
			dcbBaudRate = CBR_1200
		Case 2400
			dcbBaudRate = CBR_2400
		Case 4800
			dcbBaudRate = CBR_4800
		Case 9600
			dcbBaudRate = CBR_9600
		Case 14400
			dcbBaudRate = CBR_14400
		Case 19200
			dcbBaudRate = CBR_19200
		Case 38400
			dcbBaudRate = CBR_38400
		Case 56000
			dcbBaudRate = CBR_56000
		Case 57600
			dcbBaudRate = CBR_57600
		Case 115200
			dcbBaudRate = CBR_115200
		Default
			Return INVALID_HANDLE_VALUE
	End Select
	
	driverHandle = apiCreateFile("COM"+comport, GENERIC_READ Or GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0)
	If driverHandle = INVALID_HANDLE_VALUE Then
		Return INVALID_HANDLE_VALUE
	Else
		apiSetupComm(driverHandle, 1024, 1024)

		dcb = CreateBank(28)
		
		PokeInt dcb, 00, 28                         ; sizeof(DCB)
		PokeInt dcb, 04, dcbBaudRate                ; current baud rate

		val	= 1										; Binary Mode (skip Eof check)    
		If parityEnable	= True Then val = val Or 2	; Enable parity checking
		If protocol		= DTR_CONTROL Then val = val Or 48	; DTR Flow control on
		PokeByte dcb, 08, val
		
		val = 0
		If protocol = RTS_CONTROL Then val = val Or 48
		PokeByte dcb, 09, val

		PokeByte dcb, 18, dataBits					; number of bits/byte, 4-8
		PokeByte dcb, 19, parityBit					; 0-4=no, odd, even, mark, space
		PokeByte dcb, 20, stopBits					; 0,1,2 = 1, 1.5, 2

		apiSetCommState(driverHandle, dcb)
		apiSetCommMask(driverHandle, EV_TXEMPTY)

	EndIf
   
	FreeBank dcb
	Return driverHandle
	
End Function

After looking some more, it appears that you are already doing so.
The com settings DO change because I've used Vertexes code. I'm not sure what your code to return the com settings actually returns.