>>Hi there,
>>
>>I want to send data through the com-port to a customer-display.
>>I know that I can use mscoom.ocx or something similar but as I am trying
>>to avoid using controls I was wondering if there is a win-api I could use directly?
>>
>>Thanks in advance
>>
>>Thomas
>
>There was track D-TIP1 on the DFPUG DevCon 2016, doing the job with WIN32API. PM me, if you need it.
>
>Lutz

some of the API declarations you'll need are:

    DECLARE LONG  CreateFile         IN WIN32API ;
        STRING cPortName, LONG nAcess, LONG nShare, STRING cSecurity, ;
        LONG nCreate, LONG nAttrib, LONG nTemplate
    DECLARE LONG  CloseHandle        IN WIN32API LONG nHandle
    DECLARE LONG  ReadFile           IN WIN32API ;
        LONG nHandle, STRING @cBuf, LONG nLen, LONG @nRead, STRING @cOverlap
    DECLARE LONG  WriteFile          IN WIN32API ;
        LONG nHandle, STRING cBuf, LONG nLen, LONG @nWrite, STRING @cOverlap
    DECLARE LONG  FlushFileBuffers   IN WIN32API LONG nHandle
    DECLARE LONG  PurgeComm          IN WIN32API LONG nHandle, LONG nAction
    DECLARE SHORT SetCommState       IN WIN32API LONG nHandle, STRING cDCB
    DECLARE SHORT GetCommState       IN WIN32API LONG nHandle, STRING @cDCB
    DECLARE SHORT EscapeCommFunction IN WIN32API LONG nHandle, LONG nFunc
    DECLARE LONG  GetLastError       IN WIN32API
    DECLARE LONG  GetCommTimeouts    IN WIN32API ;
        LONG nHandle, STRING @cTmOutStruc
    DECLARE LONG  SetCommTimeouts    IN WIN32API ;
        LONG nHandle, STRING @cTmOutStruc
    DECLARE LONG  GetCommMask        IN WIN32API LONG nHandle, LONG @nMask
    DECLARE LONG  SetCommMask        IN WIN32API LONG nHandle, LONG nMask
    DECLARE LONG  WaitCommEvent      IN WIN32API ;
        LONG nHandle, LONG @nMask, STRING @cOverlap
    DECLARE LONG  SetCommBreak       IN WIN32API LONG nHand
    DECLARE LONG  ClearCommBreak     IN WIN32API LONG nHand
    DECLARE LONG  CancelIo IN WIN32API LONG nHand

Yep. I've written some code using API calls for serial, and wrote a similar one for winsock too. Unfortunately can't give out the code (as the code is considered property of my employer). The VFP code was near complete rewrite of the code I originally wrote for FPW (this was necessitated by a very different API). One warning however -- going this route is probably not for the faint of heart, and does require some familiarity with C/C++ (since most API examples are for that language, and you'll need to refer to many of the #define from several .h files from the C/C++ compiler).