rs232_api.pas

GSM MODEM的收发短信息

unit Rs232_Api;

interface

uses
  Windows, Variants, SysUtils, Forms, pub_Funcs, Dialogs;

const
  // 设备调用正常返回码
  DEVICE_NORMAL = 0;
  // 超时
  E_TIMEOUT = 999;
  // 端口初始化失败
  E_PORT_INIT = 998;
  // 设备尚未初始化
  E_DEVICE_BEFORE_INIT = 997;
  // 无效操作
  E_VOID_ACTION = 996;

  // 打印机少纸
  W_LOW_PAPE = 19001;
  // 打印机缺纸
  E_NO_PAPE = 18001;
  // 打印机卡纸
  E_JAM_PAPE = 18002;


type
  BYTES = array[1..255] of Byte;
  TBYTES = ^BYTES;

var
  CommHandle: THandle;
  Connected: Boolean;
  PostEvent: THandle;
  ReadOs: Toverlapped;
  Receive: Boolean;
  ReceiveData: Dword;
  szInputBuffer: Pointer;
  Check_ErrorSum: integer;
  DeviceLastError: integer;
  ResponseData: array[0..255] of Byte;

function OpenCom(Port: pchar): integer; //打开串口

function CloseCom(): integer; //关闭串口

function ReadProcess(Timeout: integer): string; //以下是实际的读取动作,读取线程函数

function SendData(strOrder: string): Boolean; //发送数据

implementation

function OpenCom(Port: pchar): integer;
var
  CommTimeOut: TCOMMTIMEOUTS;
  DCB: TDCB;
  ComStr: string;
begin
  //发送消息的句柄
  PostEvent := CreateEvent(nil, True, True, nil);
  if PostEvent = null then begin
    DeviceLastError := E_PORT_INIT;
    Result := -1;
    Exit;
  end;

  //Overlapped Read建立句柄
  ReadOs.hEvent := CreateEvent(nil, True, FALSE, nil);
  if ReadOs.hEvent = null then begin
    //MessageBox(0, 'CreateEvent Error!', 'Notice', MB_OK);
    DeviceLastError := E_PORT_INIT;
    CloseHandle(PostEvent);
    Result := -1;
    Exit;
  end;

  //建立串口句柄
  CommHandle := CreateFile(Port, GENERIC_WRITE or GENERIC_READ,
    0, nil, OPEN_EXISTING, FILE_FLAG_OVERLAPPED or FILE_ATTRIBUTE_NORMAL, 0);

  if CommHandle = INVALID_HANDLE_VALUE then begin
    CloseHandle(PostEvent);
    CloseHandle(ReadOs.hEvent);
    DeviceLastError := E_PORT_INIT;
    Result := -1;
    Exit;
  end;

  //设置超时
  CommTimeOut.ReadIntervalTimeout := MAXDWORD;
  CommTimeOut.ReadTotalTimeoutMultiplier := 0;
  CommTimeOut.ReadTotalTimeoutConstant := 0;
  SetCommTimeouts(CommHandle, CommTimeOut);

  //设置读写缓存
  SetupComm(CommHandle, 4096, 1024);

  //对串口进行指定配置
  GetCommState(CommHandle, DCB);
  DCB.BaudRate := 9600;
  DCB.ByteSize := 8;
  DCB.Parity := 0; ;
  DCB.StopBits := 0;
  Connected := SetCommState(CommHandle, DCB);

  //关系串口的读事件
  if (not SetCommMask(CommHandle, EV_RXCHAR)) then begin
    DeviceLastError := E_PORT_INIT;
    Result := -1;
    Exit;
  end;

  if (Connected) then begin
    Connected := True;
    Result := 0;
  end
  else begin
    CloseHandle(CommHandle);
    Result := -1;
  end;
end;

function CloseCom(): integer;
begin
  if CommHandle <> INVALID_HANDLE_VALUE then begin
    CloseHandle(CommHandle);
    CommHandle := INVALID_HANDLE_VALUE;
  end;
  Result := 0;
end;

//以下是实际的读取动作,读取线程函数

function ReadProcess(Timeout: integer): string;
var
  CommState: ComStat;
  dwNumberOfBytesRead: Dword;
  ErrorFlag: Dword;
  InputBuffer: Pointer; //array[0..1024] of Char;   此处改用指针的方式，便于后续16制显示 jtp
  lpszPostedBytes: LPSTR;

  _Buffer: TBYTES;
  _ByteStr: AnsiString;
  tmpStr: string;
  temp: string;

  j, i: integer;
  EndTime: Dword;
begin

  if CommHandle = INVALID_HANDLE_VALUE then begin
    DeviceLastError := E_DEVICE_BEFORE_INIT;
    Result := '';
    Exit;
  end;

  EndTime := GetTickCount + Timeout;
  while GetTickCount < EndTime do begin
    Application.ProcessMessages;
    ClearCommError(CommHandle, ErrorFlag, @CommState);
    //if CommState.cbInQue > 0 then break;
  end;
  if not ClearCommError(CommHandle, ErrorFlag, @CommState) then begin
    DeviceLastError := E_DEVICE_BEFORE_INIT;
    Result := '';
    PurgeComm(CommHandle, Purge_Rxabort or Purge_Rxclear);
    Exit;
  end;



  if CommState.cbInQue > 0 then begin
    GetMem(InputBuffer, CommState.cbInQue + 1);
    if (not ReadFile(CommHandle, InputBuffer^, CommState.cbInQue,
      dwNumberOfBytesRead, @ReadOs)) then begin
      ErrorFlag := GetLastError();
      if (ErrorFlag <> 0) and (ErrorFlag <> ERROR_IO_PENDING) then begin
        DeviceLastError := E_PORT_INIT;
        Result := '';
        Receive := FALSE;
        CloseHandle(ReadOs.hEvent);
        CloseHandle(PostEvent);
        CloseHandle(CommHandle);
        Exit;
      end
      else begin
        WaitForSingleObject(CommHandle, INFINITE); // 等待操作完成
        GetOverLappedResult(CommHandle, ReadOs, dwNumberOfBytesRead, FALSE);
      end;
    end;
    if dwNumberOfBytesRead > 0 then begin
      ReadOs.Offset := ReadOs.Offset + dwNumberOfBytesRead;
      ReceiveData := ReadOs.Offset;
      // 处理接收的数据
      _Buffer := InputBuffer;
      _ByteStr := '';
      j := 0;
      for i := 1 to dwNumberOfBytesRead do begin
        _ByteStr := _ByteStr + IntToHex(_Buffer^[i], 2);
        ResponseData[j] := _Buffer^[i];
        inc(j);
      end;
    end
    else begin
      DeviceLastError := E_TIMEOUT;
      Result := '';
    end;
    FreeMem(InputBuffer);
  end;
  Result := _ByteStr;
end;


function SendData(strOrder: string): Boolean;
var
  strOrderByte: array[0..128] of Byte;
  lrc: LongWord;
  Str: TBlocka;
  i: integer;
  writeoverlapped: Toverlapped;
  ByteToWrite, BytesWritten, AllBytesWritten: Dword;
  ErrorCode, ErrorFlag: Dword;
  CommStat: ComStat;
begin

  //Str := myHextoStr(strOrder);
  //Str := strOrder;
  Str := HexTobytearray(strOrder);
  Result := True;
  if CommHandle = INVALID_HANDLE_VALUE then begin
    Result := FALSE;
    DeviceLastError := E_DEVICE_BEFORE_INIT;
    Exit;
  end;
  ByteToWrite := Length(strOrder) div 2;
  try
    //初始化一步读写结构
    FillChar(writeoverlapped, SizeOf(writeoverlapped), 0);
    //避免贡献资源冲突
    writeoverlapped.hEvent := CreateEvent(nil, True, FALSE, nil);
    //发送数据
    if not WriteFile(CommHandle, Str, ByteToWrite, BytesWritten, @writeoverlapped) then begin
      ErrorCode := GetLastError;
      if ErrorCode <> 0 then begin
        if ErrorCode = ERROR_IO_PENDING then begin
          //StatusBar1.SimpleText := '端口忙，正在等待...';

          while not GetOverLappedResult(CommHandle, writeoverlapped, BytesWritten, True) do begin
            ErrorCode := GetLastError;
            if ErrorCode = ERROR_IO_PENDING then
              continue
            else begin
              ClearCommError(CommHandle, ErrorFlag, @CommStat);
              DeviceLastError := E_VOID_ACTION;
              Result := FALSE;
              CloseHandle(writeoverlapped.hEvent);
              CloseHandle(CommHandle);
              Exit;
            end;
          end;
          AllBytesWritten := AllBytesWritten + BytesWritten;
        end
        else begin
          ClearCommError(CommHandle, ErrorFlag, @CommStat);
          DeviceLastError := E_VOID_ACTION;
          Result := FALSE;
          CloseHandle(writeoverlapped.hEvent);
          Receive := FALSE;
          CloseHandle(CommHandle);
          CloseHandle(PostEvent);
          Exit;
        end;
      end;
    end;
  finally
    CloseHandle(writeoverlapped.hEvent);
  end;
end;

procedure Delay(waittime: integer);
var
  EndTime: Dword;
begin
  EndTime := GetTickCount + waittime;
  while GetTickCount < EndTime do Application.ProcessMessages;
end;

function InsertLogfile(log_str: string): Boolean;
var
  F: TextFile;
  MyStr: string;
  sss: string;
  FileHandle: integer;
begin

  try
    sss := FormatDateTime('yyyy-mm-dd', Now) + '.txt';
    if not FileExists(sss) then begin
      FileHandle := FileCreate(sss);
      FileClose(FileHandle);
    end;
    AssignFile(F, sss);
    Append(F);
    MyStr := FormatDateTime('yyyy-mm-dd hh:mm:ss', Now) + chr(9) + log_str;
    Writeln(F, MyStr);
    Flush(F);
    CloseFile(F);
  except
    Result := FALSE;
  end;
  Result := True;
end;

end.