i found this code in one example for TMSA32 component:

procedure TfrmMain.ButtonOpenClick(Sender: TObject);
begin
VaComm1.Open;
Comm1Dsr(VaComm1);
end;

procedure TfrmMain.Comm1Dsr(Sender: TObject);
begin
if VaComm1.DSR then
StatusBar1.Panels[1].Text := 'DSR'
else StatusBar1.Panels[1].Text := '';
end;

Where Vacomm is component.
In events for Vacomm1 in the first column is OnDsr,and next to him(aprpriate to him is Comm1Dsr) is CommDsr.In help i find this:

property OnDsr: TNotifyEvent;
Description
The DSR (data-set-ready) signal changed state.

Does above code mean that Comm1Dsr(VaComm1);
call TfrmMain.Comm1Dsr?

Please answer me

it calls the instance of frmMain's Comm1Dsr, if you had 2 instances of your form, it would only call the procedure in one of those forms.