Urgent: Serial port call failed?

Ankoku

Attendance machine dynamic library description:
Explanation: All functions only accept two parameters
Parameter one: Params structure
Parameter 2: A value indicating the type of hardware, value [30, 60, 2000, 2100, 2200, 2300, 2600]

Params structure definition
Public Type Params
    Port As String * 3 // Serial port number, [1 ~ 255]
    CtrlID As String * 3 // device number, [1 ~ 127]
    Params As String * 1024 // Input: The parameter table passed to the device for processing. Multiple parameters are separated by semicolons and terminated with semicolons.
                           // Output: Interface return value
End Type

Interface return value definition
100 // Failed to call the interface
101 // This type of device is not supported
102 // The device does not support this interface
103 // The device is not responding
104 // parameter error
105 // The call was successful
106 // The serial port is not open
107 // Error opening file
108 // Communication parameter error, request resend
109 // Return value data check error
110 // Create thread error
111 // The device is busy

I. IT2100
Open serial port
statement
Public Declare Function OpenComm Lib "CM60.dll" (ByRef lParam As Params, ByVal sType As Integer) As Integer
Call example
dim p as Params
dim sType as Integer
dim ret as Long

sType = 2100
p.Port = "001" ‘Open serial port one
p.CtrlID = "001" ‘device number is 1

ret = OpenComm (p, sType)
select case ret
case 100 ‘Open failed
case 105 ‘Successful opening of serial port
case else
    end select




I tested:
unit Ukq;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class (TForm)
    Button1: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    procedure Button1Click (Sender: TObject);
  
  private
    {Private declarations}
  public
    {Public declarations}
  end;

type
  TParams = Record
    Port: String [3];
    CtrlID: String [3]; // device number, [1 ~ 127]
    Params: string [250];
  end;

var
  Form1: TForm1;


implementation

{$ R * .dfm}
function OpenComm (var lParam: tParams; sType: Integer): Integer; stdcall; external 'CM60.dll';
function CloseComm (var lParam: tParams; sType: Integer): Integer; stdcall; external 'CM60.dll';

procedure TForm1.Button1Click (Sender: TObject);
var
  p: TParams;
  sType, ret: Integer;
begin
  sType: = 2100;
  p.Port: = edit1.text;
  p.CtrlID: = edit2.Text;
  ret: = OpenComm (p, sType);
    showmessage (inttostr (ret));


  ret: = CloseComm (p, sType);
   p.CtrlID: = '';
    showmessage (inttostr (ret));
 
end;
end.


Opening and closing the serial port both returned 100 (failed to call the serial port), and using the terminal management of the time attendance machine can open the first and second serial ports, I do n’t know if there is something wrong with my test program

stevevai

Open the serial port, are you sure that no other program is occupying the serial port you want to open,

Ankoku

No, I can use the terminal management of the attendance machine to open the first and second serial ports, which can be closed

72次灌水被抓

PParams = ^ TParams;
var p: PParams; OpenComm (p, sType);
Or p: TParams; OpenComm (^ p, sType);
The first parameter of OpenComm is the address

Ankoku

PParams = ^ TParams;
var p: PParams; OpenComm (p, sType);
Or p: TParams; OpenComm (^ p, sType);
The first parameter of OpenComm is the address

After changes, the editor prompts an error: types of actual and formal var parametes must be identical

stevevai

It is a reference by address, but var is also used in the declaration of delphi, which already corresponds to the byref of VB.
The problem is not here, should your serial device parameters be set in the Params character array in the TPams record?

Ankoku

Modified to the following code:

unit Ukq;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class (TForm)
    Button1: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    procedure Button1Click (Sender: TObject);
  
  private
    {Private declarations}
  public
    {Public declarations}
  end;

type
  TParams = Record
    Port: String [3];
    CtrlID: String [3]; // Device number, [1 ~ 127]
    Params: string [250];
  end;

  pparams = ^ TParams;

var
  Form1: TForm1;


implementation

{$ R * .dfm}
function OpenComm (var lParam: pParams; sType: Integer): Integer; stdcall; external 'CM60.dll';
function CloseComm (var lParam: pParams; sType: Integer): Integer; stdcall; external 'CM60.dll';

procedure TForm1.Button1Click (Sender: TObject);
var
  p: pparams;
  sType, ret: Integer;
begin
  sType: = 2100;
  p.Port: = edit1.text;
  p.CtrlID: = edit2.Text;

  ret: = OpenComm (p, sType);
    showmessage (inttostr (ret));


  ret: = CloseComm (p, sType);
   p.CtrlID: = '';
    showmessage (inttostr (ret));
 
end;

end.

The edit was successful, and when running, access violation at address 0040211 ... address error

Ankoku

00402A11,0042C590

Ankoku

Is in p.Port: = edit1.text;
  p.CtrlID: = edit2.Text;
There is an address error in these two places, it is the same to change to p.port: = '001'