serial port properties

[Rik]

Elsewhere in this forum (https://forum.lazarus.freepascal.org/index.php/topic,16616.msg90544.html#msg90544) I found a script that return the friendly name of a serial port via the Windows Registry.
The friendly name is retrieved using the TRegistry.ReadString('FriendlyName') function.
I would expect that it is possible to retrieve other serial port properties as wel via the ReadString function?
With properties I mean those that can be found via the Device Manager -> Ports (COM & LPT)-> Device -> Properties -> Details.
As a quick and dirty test I tried to get the Device description using TRegistry.ReadString('DeviceDescription'), but that failed.

Is it possible to retrieve other properties as wel via the ReadString function?
If so, where can I find a list of the strings to be used and the corresponding properties?
.

[gues1]

All Hardware properties (where settings were maintained) are described in the key:

HKLM/System/CurrentControlSet/Enum

But more subkey are locked (you neede special auth to access them, admin is not enough).

You can access to these data and more via WMI interface, here one example: https://theroadtodelphi.com/category/wmi/

For serial port you can also open all of them and read directly the properties, but you will not know the limits (for example maximun baud rates supported).

[Rik]

All Hardware properties (where settings were maintained) are described in the key: HKLM/System/CurrentControlSet/Enum

Indeed, but I already tried that ...

But more subkey are locked (you neede special auth to access them, admin is not enough)

.. and got stuck on an access denied error for the subkey Properties, even with admin privileges.

You can access to these data and more via WMI interface

That's new stuff to me, I'll have a look at it.

[Rik]

WMI is not needed for what I was looking for.
The funcion TRegistry.GetValueNames: TUnicodeStringArray returns the names of all available properties of the serial port.

[CM630]

I use this:

Code: Pascal  [Select][+][-]

1. function GetComFriendlyName (PortName : string) : String;
2. var
3.   Registry : TRegistry;
4.   PortType: String = '';
5.   VID_PID: String = '';
6.   ID: string = '';
7.   Contents : array of String;
8.   KeyName: String = '';
9. begin
10.   Result := '';
11.   Registry := TRegistry.Create(KEY_READ);
12.   try
13.     Registry.RootKey := HKEY_LOCAL_MACHINE;
14.     if Registry.OpenKey('\SYSTEM\ControlSet001\Control\COM Name Arbiter\Devices',False) then
15.     begin
16.       Contents := Registry.ReadString(PortName).Split(['#']);
17.       if (Length(Contents) > 2) then
18.       begin
19.         PortType := copy(Contents[0],5,MaxInt) ;
20.         VID_PID := Contents[1];
21.         ID := Contents[2];
22.         KeyName := '\SYSTEM\ControlSet001\Enum\' + PortType + '\' + VID_PID + '\' + ID;
23.         if Registry.OpenKey(KeyName,False) then
24.           Result := Registry.ReadString('FriendlyName');
25.       end; //Length
26.     end; //if Registry.OpenKey
27.   finally
28.     Registry.Free;
29.   end; //try
30. end;
31.  
32. procedure TForm1.FormCreate(Sender: TObject);
33. begin
34.   ShowMessage (GetComFriendlyName('COM51'));
35. end;

I get the port names from GetSerialPortNames, which is a routine of the multiplatform TLazSerial.
How to get friendly names in Linux (if they exist) - I do not know.

[gues1]

WMI is not needed for what I was looking for.
The funcion TRegistry.GetValueNames: TUnicodeStringArray returns the names of all available properties of the serial port.

Good to know.

[jamie]

https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-getcommports

states you need windows 10 min. so just an idea..

Jamie

[Jurassic Pork]

WMI is not needed for what I was looking for.

Hello,
Maybe : it is what you are looking for 
With this code , i can retrieve some properties of my Serial ports on Windows 11 with Lazarus 3.6 .

Code: Pascal  [Select][+][-]

1. implementation
2. uses contnrs,utilwmi;
3. {$R *.lfm}
4. { TForm1 }
5. procedure TForm1.Button5Click(Sender: TObject);
6. var
7.   WMIResult         : TFPObjectList;
8.   i                 : Integer;
9.   PropNamesIndex    : Integer;
10.   PropNames         : Array[0..4] of String =
11.                       ( 'Manufacturer','Caption','Name',
12.                         'Description','DeviceID');
13.   PropName       : String;
14.   PropValue      : String;
15. begin
16.     WMIResult := GetWMIInfo('Win32_PnPEntity', PropNames,
17.                  'Where PnpClass = ''Ports'' ');
18.                  // 'Where Name LIKE ''%(COM%'' ');
19.   for i := 0 to Pred(WMIResult.Count) do
20.   begin
21.     Memo1.Append('================================================');
22.     for PropNamesIndex := Low(PropNames) to High(PropNames) do
23.     begin
24.       PropName :=   TStringList(WMIResult[i]).Names[PropNamesIndex];
25.       PropValue :=   TStringList(WMIResult[i]).ValueFromIndex[PropNamesIndex];
26.       Memo1.Append(PropName + ' : ' +
27.               PropValue);
28.     end;
29.   end;
30.   // Clean up
31.   WMIResult.Free;
32. end;  

Manufacturer : FTDI
Caption : USB Serial Port (COM5)
Name : USB Serial Port (COM5)
Description : USB Serial Port
DeviceID : FTDIBUS\VID_0403+PID_6001+6&1FEC562&7&1\0000
================================================
Manufacturer : FTDI
Caption : USB Serial Port (COM6)
Name : USB Serial Port (COM6)
Description : USB Serial Port
DeviceID : FTDIBUS\VID_0403+PID_6001+6&1FEC562&7&2\0000

In attachment in a zip file my utility  utilwmi.

Not sure that it is OK with "Hardware serial ports" (not USB - i can't check) .

Friendly, J.P