怎么调用fzclient.dll初始化刷卡器

[weixin_37016780]

delphi7声明部分：
var
Form1: TForm1;
function ykt_opendevice(nDeviceType:integer;nCom:integer;nBaud:integer;pRegion:PChar;pWanrnmsg:PChar;pErrmsg:PChar):integer; stdcall; external '.\fzyktclient.dll';
implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var nDeviceType:integer;
nCom:integer;nBaud:integer;
pRegion:PChar;
pWanrnmsg:PChar;
pErrmsg:PChar;
flag:integer;
begin
nDeviceType:= strtoint(edit1.text);
nCom:=strtoint(edit2.text);
nBaud:=strtoint(edit3.text);
flag:= ykt_opendevice(nDeviceType,nCom,3501, pWanrnmsg,pWanrnmsg); //这句出错
showmessage(inttostr(flag))
end;

另外怎么用edit.text给PChar传递参数？
PChar怎么初始化和释放内存空间？
ykt_opendevice(nDeviceType,nCom,3501, pWanrnmsg,pWanrnmsg); pWanrnmsg和pErrmsg的值如何获取到？

[weixin_37016780]

现在报错提示 [Error] Unit1.pas(60): Incompatible types: 'Integer' and 'PAnsiChar'