Spcomm串口控件的例程

procedure TForm1.BitBtn3Click(Sender: TObject);
   begin
   comm1.startcomm;
   end;
  //关闭串口
   procedure TForm1.BitBtn4Click(Sender: TObject);
   begin
   comm1.StopComm;
   end;
   //发送数据
   procedure TForm1.BitBtn1Click(Sender: TObject);{var str:string;
ch1:char;
   begin
   comm1.WriteCommData(ch,1);
   end.
   //接收数据
   procedure TForm1.Comm1ReceiveData(Sender: TObject; Buffer: Pointer;
  BufferLength: Word);
   type   ss=array[1..500]of char ;
   var str1:^ss;
i:integer;
s:array[0..15] of char ;
n:integer;
   begin
str1:=Buffer;
  //s[]=('0','1','2','3'...'E')
for i:=0 to 9 do
s[i]:=chr(48+i);
for i:=10 to 15 do
s[i]:=chr(55+i);
for i:=1 to bufferlength do
begin
n:=ord(str1^[i]);
listbox1.Items.add(
  inttostr(listbox1.Items.Count+1)
  +' - '+s[n div 16]+s[n mod 16]);
end;
listbox1.Refresh;
   if listbox1.Items.count > strtoint(form2.edit1.text)
   then listbox1.Items.Clear;
   end;