Re: [Dev-C++] Modem Configuration

[Abhijit S. <mu...@gm...>]

----- Original Message -----
From: "Evandro Humberto Rodrigues" <ero...@ro...>
To: <Dev...@li...>
Sent: Wednesday, September 11, 2002 9:43 PM
Subject: [Dev-C++] Modem Configuration


Hi people,

    I trying to produce a little program to configurate my external modem
(USR 56K).
    First I create a file with CreateFile() function, then I used
WriteFile() function to send the configuration strings to modem.
    For test I sent a string like "ATDT 9092" to put the modem to dial to
the number 9092, but the ligths on the modem blink but modem does not make
the call...
    Using HYPERTERMINAL, this work fine.
    What is wrong?
    I put the program below if someone can help me I will be grateful.

---------- program -------------------------

#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <windows.h>
#include <string>

int main(int argc, char *argv[])
{
  DCB dcb;
  HANDLE hCom;
  BOOL fSuccess;
  LPCVOID buffer;
  char *pcCommPort = "COM2";

  using namespace std;

  hCom = CreateFile( pcCommPort,
                     GENERIC_READ | GENERIC_WRITE,
                     0,    // comm devices must be opened w/exclusive-access
                     NULL, // no security attributes
                     OPEN_EXISTING, // comm devices must use OPEN_EXISTING
                     0,    // not overlapped I/O
                     NULL  // hTemplate must be NULL for comm devices
                     );

  if (hCom == INVALID_HANDLE_VALUE) {
      // Handle the error.
      printf ("CreateFile failed with error %d.\n", GetLastError());
      return (1);
    }

  // We will build on the current configuration, and skip setting the size
  // of the input and output buffers with SetupComm.

  fSuccess = GetCommState(hCom, &dcb);

  if (!fSuccess) {
      // Handle the error.
      printf ("GetCommState failed with error %d.\n", GetLastError());
      return (2);
    }

  // Fill in the DCB: baud=57,600 bps, 8 data bits, no parity, and 1 stop
bit.

  dcb.BaudRate = CBR_57600;     // set the baud rate
  dcb.ByteSize = 8;             // data size, xmit, and rcv
  dcb.Parity = NOPARITY;        // no parity bit
  dcb.StopBits = ONESTOPBIT;    // one stop bit

  fSuccess = SetCommState(hCom, &dcb);

  if (!fSuccess) {
      // Handle the error.
      printf ("SetCommState failed with error %d.\n", GetLastError());
      return (3);
    }

  string codigo = "ATDT 9092\n";
  DWORD nBytes;
  string lida = "1234567890123456789012345678901";

  if (WriteFile(hCom, &codigo, 10, &nBytes, NULL))
    cout << "Foram escritos " << nBytes << " Bytes" << endl;

  if (ReadFile(hCom, &lida, 10, &nBytes, NULL))
    cout << "String lida -> " << lida << " Bytes lidos " << nBytes << endl;

  system("PAUSE");
  return (0);
}



-------------------------------------------------------

I don't know much about what you're doing, but I think you should try
replacing this line:

  if (WriteFile(hCom, &codigo, 10, &nBytes, NULL))

with

  if (WriteFile(hCom, codigo.c_str(), codigo.size(), &nBytes, NULL))

because you're passing the address of the class instance in the first case,
and it's different from the contents of the buffer. Same thing with
ReadFile... you can't use `string's. Try replacing the usage of the string
class with normal ASCIIZ buffers... it should work then.

There's also some incorrect usage of namespace stuff that might work in this
version of GCC, but not in all ANSI compilers... I think Ioannis will be
happy to point them out if you want... :)

HTH.

___________________________________________________________

Abhijit Shylanath

E-mail:   mu...@gm... || ibr...@bi...
Web-site: http://mudeth.tripod.com/