more CommEvents than expected

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I am receiving a lot more events from WaitCommEvent() than I expect. I think
there should be only five lines of output for status changes with COM1 inputs
as follows:
DSR pin 6 is always true
RING pin 9 goes true
CTS pin 8 goes true for only 1.5 seconds
RING pin 9 goes false
DSR pin 6 is stays true

I get some repeated lines in the following output

commStatus = 20 (okay, pin 6 was high)
ev_ring pin nine fPending = 0 commStatus = 60 (okay, pin 9 went high)
ev_ring pin nine fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 70 (okay, pin 8 went high)
ev_cts pin eight fPending = 0 commStatus = 70 (why)
ev_cts pin eight fPending = 0 commStatus = 70 (why)
ev_cts pin eight fPending = 0 commStatus = 70 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (okay, pin 8 went low)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_cts pin eight fPending = 0 commStatus = 60 (why)
ev_ring pin nine fPending = 0 commStatus = 20 (okay, pin 9 went low)

The lines marked (why) seem strange to me. What are these state changes?

Note: the WaitCommEvent is always finishing and returning no error on the
first call. This may be okay.

Note: The TX and RX lines are not connected. We are using the COM1 port as
input for a few discrete signals.

Note: Pin 4 is jumpered to Pin 6 to signal the cable is connected.

Note: The operating system is Windows XP Professional

// Here is my code

#include <windows.h>
#include <stdio.h>
#include <conio.h>

HANDLE g_hEvStop;

DWORD WINAPI ThreadProcSS(LPVOID lpvParam)
{
HANDLE hCom;
DWORD dwEvtMask = 0;
OVERLAPPED o;
BOOL fPending = 0;
DWORD dwRet;
HANDLE hArray[2];
BOOL proc;

DWORD dwCommStatus;

memset(&o, 0, sizeof(o));

o.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

if (o.hEvent == NULL)
{
printf("CreateEvent failed.\n");
return 1;
}

hCom = CreateFile("\\\\.\\COM1",
GENERIC_READ | GENERIC_WRITE,
0, // exclusive access
NULL, // no security attrs
OPEN_EXISTING,
FILE_FLAG_OVERLAPPED,
NULL);

if (hCom == INVALID_HANDLE_VALUE)
{
printf("unable to open COM port\n");
CloseHandle(o.hEvent);
return 1;
}


if (GetCommModemStatus(hCom, &dwCommStatus))
printf("commStatus = %x\n", dwCommStatus);
else
printf("Error = %d\n", GetLastError());


SetCommMask(hCom, EV_CTS | EV_DSR | EV_RING | EV_RLSD );

hArray[0] = g_hEvStop;
hArray[1] = o.hEvent;

for(;;)
{
proc = 0;

if (!fPending)
{
if (WaitCommEvent(hCom, &dwEvtMask, &o))
{
proc = 1;
}
else
{
if (GetLastError() == ERROR_IO_PENDING)
{
fPending = 1;
}
}
}
else
{
dwRet = WaitForMultipleObjects(2, hArray, FALSE, INFINITE);

if (dwRet == WAIT_OBJECT_0)
{
break;
}

if (dwRet == WAIT_OBJECT_0 + 1)
{
proc = 1;
fPending = 0;
}
}

if (proc)
{

if (dwEvtMask & EV_DSR) printf("ev_dsr pin six fPending = %d ",
fPending);
if (dwEvtMask & EV_CTS) printf("ev_cts pin eight fPending = %d ",
fPending);
if (dwEvtMask & EV_RING) printf("ev_ring pin nine fPending = %d ",
fPending);
if (dwEvtMask & EV_RLSD) printf("ev_rlsd pin one fPending = %d ",
fPending);
if (GetCommModemStatus(hCom, &dwCommStatus))
printf("commStatus = %x\n", dwCommStatus);
else
printf("Error = %d\n", GetLastError());
}
}

CloseHandle(o.hEvent);

CloseHandle(hCom);

return 0;
}

DWORD WINAPI ThreadProcKB(LPVOID lpvParam)
{
int ch;

for(;;)
{
if (kbhit())
{
ch = getch();
if (ch == 0)
ch = getch();

if (ch == 'n')
printf("-------\n");
else
{
SetEvent(g_hEvStop);
break;
}
}
else
{
Sleep(10);
}
}

return 0;
}

int main(void)
{
HANDLE hThreadKB;
HANDLE hThreadSS;
DWORD dwThreadIDKB;
DWORD dwThreadIDSS;
HANDLE hArray[2];

g_hEvStop = CreateEvent(NULL,TRUE,FALSE,NULL);

hThreadKB = CreateThread(NULL, 0, ThreadProcKB, 0, 0, &dwThreadIDKB);

hThreadSS = CreateThread(NULL, 0, ThreadProcSS, 0, 0, &dwThreadIDSS);

hArray[0] = hThreadKB;
hArray[1] = hThreadSS;

WaitForMultipleObjects(2, hArray, FALSE, INFINITE);

CloseHandle(g_hEvStop);
CloseHandle(hThreadKB);
CloseHandle(hThreadSS);

return 0;
}

.

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