Re: Visual C++ MSComm activex Control problem

I am having problems with the MSComm control in visual C++ 6.0 I have
gotten it to transmit data but to my surprise it does not recive proporly
every byte i send it.
I am confounded on this one. I noticed that when trying to send
0x99 (Hex 99) I was receiving 0x22. So I investigated further by
sending out all 256 bytes of data 0x00 thru 0xFF. I used the MSCom
control to send out the signal in one program and another MSComm control
to receive the signal in my second program. I simply used a loop back
cable between the two serial ports. Using VB (Still the MSComm control
set the same way) to receive I received the data correctly, I concluded
that it wasn't my transmitting program that was at fault. using the VC
receiving program however the incoming results are as follows.

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F
20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F
30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F
40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F
60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F
70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F
AC 81 1A 92 1E 26 20 21 C6 30 60 39 52 8D 7D 8F
90 18 19 1C 1D 22 13 14 DC 22 61 3A 53 9D 7E 78
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF
B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF
C0 C1 C2 C3 C4 C5 C6 C7 C8 C9 CA CB CC CD CE CF
D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB DC DD DE DF
E0 E1 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF
F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 FA FB FC FD FE FF

If you notice all of the data came thru fine except for in the range
between 0x7F and 0xA0. The above data is consistent i.e. I always get
0xAC when expecting 0x80. Using a Port monitor (Portmon
http://www.sysinternals.com) I saw that the data on the two ports were
what was to be expected. This makes me believe that the problem is
somewhere in one of the settings of the control or the somewhere in the
COleVariant that I pass it. here is some of the code I used in Visual
C++ 6.0

file://Set up the serial port located in OnInitDialog
 m_MSComm.SetCommPort(2);
 m_MSComm.SetSettings("38400,N,8,1");
 m_MSComm.SetInputMode(0); file://comInputModeText
 m_MSComm.SetHandshaking(0); file://no Handshaking
 m_MSComm.SetInBufferSize(1024); file://Set Inbuffer to 1024
 m_MSComm.SetOutBufferSize(512); file://Set Outbuffer to 512
 m_MSComm.SetInputLen(1); file://Set InputLength to 1
 m_MSComm.SetRThreshold(1); file://Set Recive Threshold to 1
 m_MSComm.SetSThreshold(1); file://Set Send Threshold to 1
 m_MSComm.SetDTREnable(FALSE); file://Set DTR OFF
 m_MSComm.SetRTSEnable(TRUE); file://Set RTS ON
 m_MSComm.SetPortOpen(TRUE); file://Set Port open

file://Here is the OnMSComm routine
file://m_RcvdData is the member variable attached to the main editbox
void CLoggerEmulatorDlg::OnOnCommMscomm()
{
 unsigned char cTemp;
 COleVariant cvTemp;
 CString csTemp;
 int i;

 while(m_MSComm.GetInBufferCount()>0)
 {
   UpdateData(TRUE);
   while(m_MSComm.GetInBufferCount()>0)
   {
    cvTemp = m_MSComm.GetInput(); file://returns a Variant
    cTemp = (unsigned char )(*cvTemp.bstrVal);//look at variant.bstrVal
    i = 0;
    if (cTemp == 0x7F)
    {
     i = 0;
    }
    csTemp.Format("%2.2X ",cTemp);
    m_RcvdData = m_RcvdData + csTemp;

   }
   m_RcvdData = m_RcvdData + CString("\r\n");
   UpdateData(FALSE);
 }//end while
}

The GetInput member function will return a variant. Which i store in a
COleVariant variable. This i use to extract the Byte that I am
expecting. InLength is set to 1 and InputMode is set to text.

any help you can get i will apreciate. I have run out of ideas of where
to look for my fault.

Thanks Jacob Scarpaci