hi,

i want send strings by a port COM and put the RTS signal to 1 before send,
and put it to 0 after send the last caractere. A extract of my code:

DWORD dwEvtMask;
char *bufferS = "toto";

hPort  = CreateFile
( "COM1", GENERIC_WRITE|GENERIC_READ,0, NULL, OPEN_EXISTING,        
FILE_FLAG_OVERLAPPED, );
         
SetCommMask(hPort, EV_TXEMPTY)
   
overloppedAttEnvoi.hEvent = CreateEvent(NULL, true, 0, NULL);
overloppedAttEnvoi.Internal = 0;
overloppedAttEnvoi.InternalHigh = 0;
overloppedAttEnvoi.Offset = 0;
overloppedAttEnvoi.OffsetHigh = 0;
   
overloppedEcri.hEvent = CreateEvent(NULL, false, 0, NULL);
overloppedEcri.Internal = 0;
overloppedEcri.InternalHigh = 0;
overloppedEcri.Offset = 0;
overloppedEcri.OffsetHigh = 0;   
   
EscapeCommFunction(hPort,SETRTS)
   
WriteFile(hPort, bufferS, nbCharAEcrire, &nbCharEcrit, &overloppedEcri)
   
WaitCommEvent(hPort, &dwEvtMask, &overloppedAttEnvoi)
iLastErr = GetLastError();
if (iLastErr != ERROR_IO_PENDING)
               printf ("Probleme! %i\n",iLastErr);
else
{
rap = WaitForSingleObject(overloppedAttEnvoi.hEvent, 1000);    
    switch (rap)
    {
    case WAIT_OBJECT_0:        
        if (!GetOverlappedResult(hPort, &overloppedAttEnvoi, &nbCharEcrit, false))
        {
        iLastErr = GetLastError();  
        if (iLastErr == ERROR_IO_INCOMPLETE)
           printf("%s %d","Operation incomplete",iLastErr);
        else
           printf ("Error : %x et rap : %d\n" , GetLastError(),rap);
        }
        else
        {
        ResetEvent(overloppedAttEnvoi.hEvent);
        EscapeCommFunction(hPort,CLRRTS)            }break;
                   default:
        printf ("Error : %x et rap : %d\n" , GetLastError(),rap);
        }
    }
   

Normaly i put RTS to 0 when the last caractere sent, but NO!
RTS down low at the midle of my string!!!

Help me please to resolve this problem

Thanks.