#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <iostream>
#include <cstdio>
#include <vector>
#include <set>
#include <queue>
#include <map>
#include <string>
#include <cmath>
#include <functional>
#include <algorithm>
#include <utility>
#include <stack>
#include <unordered_map>
#include <iterator>
#include <fstream>
#include <iomanip>
#include <windows.h>

using namespace std;

#define X real()
#define Y imag()
#define timer fghge
#define y1 yjyjyju
#define all(X) (X).begin(), (X).end()
#define int long long
#define double long double

signed main() {

	HANDLE hComm;
	LPCTSTR sPortName = L"COM3";
	hComm = CreateFile(sPortName, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);

	if (hComm == INVALID_HANDLE_VALUE)
		printf("Error in opening serial port");
	else
		printf("opening serial port successful");

	DCB dcbSerialParams = { 0 }; // Initializing DCB structure
	dcbSerialParams.DCBlength = sizeof(dcbSerialParams);

	dcbSerialParams.BaudRate = CBR_9600;  // Setting BaudRate = 9600
	dcbSerialParams.ByteSize = 8;         // Setting ByteSize = 8
	dcbSerialParams.StopBits = ONESTOPBIT;// Setting StopBits = 1
	dcbSerialParams.Parity = NOPARITY;  // Setting Parity = None

	char lpBuffer[] = "A";
	DWORD dNoOFBytestoWrite;         // No of bytes to write into the port
	DWORD dNoOfBytesWritten = 0;     // No of bytes written to the port
	dNoOFBytestoWrite = sizeof(lpBuffer);
	Sleep(2000);
	WriteFile(hComm, lpBuffer, dNoOFBytestoWrite, &dNoOfBytesWritten, NULL);

	CloseHandle(hComm);
	return 0;
}