检查RS232(串口)是否接有设备
今天给大家分享的是由图老师小编精心为您推荐的检查RS232(串口)是否接有设备,喜欢的朋友可以分享一下,也算是给小编一份支持,大家都不容易啊!
MS_CTS_ON,MS_DSR_ON,MS_RING_ON,MS_RLSD_ON
procedure TForm1.Button1Click(Sender: TObject);
var
cc:TCommConfig;
hComm:THandle;
Com:String;
lS:dword;
begin
Com:='COM2';
hComm:=CreateFile(Pchar(Com),Generic_read or Generic_write,0,nil,open_existing,0,0);
if GetCommModemStatus(hcomm,lS) then
begin
if(ls and MS_CTS_ON)=MS_CTS_ON then
begin
Button1.Caption:='CTSON'
end;
end;
closeHandle(hcomm);
end;
(作者 anykey)
end.
2.检查Handle所得到的值
procedure TForm1.Button1Click(Sender: TObject);
var
cc:TCommConfig;
hComm:THandle;
Com:String;
lS:dword;
begin
Com:='COM2';
hComm:=CreateFile(Pchar(Com),Generic_read or Generic_write,0,nil,open_existing,0,0);
if(hComm=invalid_Handle_value) then
begin
showmessage('通讯口错误);
end;
closeHandle(hcomm);
end;(作者 anykey)