Re: Serial Communication in Visual C++

Right, I only initialize once. Sorry for the confusion on my part. I am
running this through a simulation environment. Initially I had the time
step set to 0.02 sec, but realized that this may be too fast for the serial
connection. However, I get the same result when setting the time step to as
slow as 2.0 secs. Each step I write the following to the serial port:

    OutputVoltage = DesiredRPM * (1/183.9);
    sprintf(buf,":CHAN1:VOLT %g",OutputVoltage);
    g_SupTalk.Write(buf, strlen(buf));

where "buf" has been declared as:

    char buf[50];
    and g_SupTalk is an instance of the class that is used

and the following is the Write function:

      int CCommTalk::Write(const char *pBuf, int nBytes) {

         DWORD ByteCount;
         CheckDelay();

         if (!WriteFile(m_hCommPort, pBuf ,nBytes, &ByteCount, NULL))
              return 0;

         return ByteCount;

     }

So, operating this way, the power supply eventually outputs the proper
desired voltage ( = "OutputVoltage"), but there is a serious delay involved.
As of now, I am not waiting for any response and am not explicitly setting
any flow control (since the power supply documentation said it didn't use
any). Also, I am performing this Write fcn each time step (just to
re-emphasize).

Thanks for the help.

-Ryan