[RESOLVED] Slow, sporadic print

OK, The app. is loaded on an XP network, with a shared USB OkiData dot matrix printer as the default printer on all PC's.
My app. simply monitors a certain folder, when a file is saved to that folder the app prints the file (via a third party application) and moves the file to another folder. Below is the code. On each PC there are two applications that are running.

There is a PointOfSale application - This is the app that writes files to the watched folder, this application is run in a Cmd window.

And the Print App - Below is the code

vb Code:

Option Explicit
    Dim DelFiles(0 To 100) As String
    Dim FS As New FileSystemObject
    Dim FSfolder As Folder
    Dim File As File
    Dim Cmd As String
    Dim ErrCnt As Integer
    Dim ErrCnt1 As Integer
    Dim strStartPath As String
    Dim ClkInt As Long
    Dim LstTen(0 To 9) As String
   
Private Sub CmdRprint_Click()
    Dim TNum As String
    Dim dFil As String
    Dim Highest As Currency
    Dim sFileName As String
    TNum = InputBox("Enter the six digit Invoice Number:", _
                        "Re-Print Ticket")
    dFil = "c:\invprnt\" & TNum & ".txt"
    TNum = "c:\bkupinv\" & TNum & ".txt"
    If MRpt.CheckFileExist(TNum) = True Then
        Call FileCopy(TNum, dFil)
        Kill TNum
    ElseIf TNum = "c:\bkupinv\747.txt" Then
        Call Form_Load
    ElseIf TNum = "c:\bkupinv\00.txt" Then
        sFileName = Dir$("c:\bkupinv\" & "*.txt", vbNormal)
        Do Until sFileName = ""
            If Val(sFileName) > Highest Then
                Highest = Val(sFileName)
            End If
            sFileName = Dir
        Loop
        Debug.Print "highest number file name = " & Highest & ".txt"
        Call FileCopy("c:\bkupinv\" & Highest & ".txt", _
                      "c:\invprnt\" & Highest & ".txt")
    Else
        MsgBox "Invalid invoice number.", vbOKOnly, "Entry error"
    End If
End Sub
 
Private Sub Form_Load()
    Dim I As Integer
    ClkInt = CLng(basRegistry.regQuery_A_Key _
            (HKEY_LOCAL_MACHINE, "SOFTWARE", "PRNTMONITOR"))
    Timer.Interval = ClkInt
    ListFolder.Interval = ClkInt
    ListFolder.Enabled = False
    Timer.Enabled = False
    strStartPath = "C:\invprnt"
    Cmd = "c:\dosprint\dosprinter /raw "
    Set FSfolder = FS.GetFolder(strStartPath)
    For I = 0 To 9
        LstTen(I) = ""
    Next
    ListFolder.Enabled = True
End Sub
 
Private Sub ListFolder_Timer()
    Dim Cnt As Integer
    Dim I As Integer
    On Error GoTo ErrorHandle
    Timer.Enabled = False
    ListFolder.Enabled = False
    Cnt = 0
    ErrCnt1 = 0
        Text1.Text = ""
        For Each File In FSfolder.Files
            DoEvents
                Text1.Text = Text1.Text & File & vbCrLf
                Shell (Cmd & File)
                DelFiles(Cnt) = File
                Cnt = Cnt + 1
        Next File
    Timer.Enabled = True
    Exit Sub
ErrorHandle:
    ErrCnt = ErrCnt + 1
    If ErrCnt < 2 Then
        ListFolder.Enabled = True
    Else
        Call MsgBox(Error & vbCrLf & "ListFolder")
    End If
End Sub
 
Private Sub Timer_Timer()
    Dim Flag As Boolean
    Dim Cnt As Integer
    On Error GoTo ErrorHandle
    ListFolder.Enabled = False
    Timer.Enabled = False
    ErrCnt = 0
    Flag = True
    Cnt = 0
    Do While Flag = True And Cnt < 101
        If IsNull(DelFiles(Cnt)) = True Or DelFiles(Cnt) = "" Then
            Flag = False
        Else
            Call FileCopy(DelFiles(Cnt), "c:\bkupinv\" & _
                            Right(DelFiles(Cnt), 10))
            Call Kill(DelFiles(Cnt))
            Cnt = Cnt + 1
        End If
    Loop
    Cnt = Cnt - 1
    Do While Cnt >= 0
        DelFiles(Cnt) = ""
        Cnt = Cnt - 1
    Loop
    ListFolder.Enabled = True
    Exit Sub
ErrorHandle:
    ErrCnt1 = ErrCnt1 + 1
    If ErrCnt1 < 2 Then
        Timer.Enabled = True
        ListFolder.Enabled = False
    Else
        Timer.Enabled = False
        ListFolder.Enabled = True
    End If
End Sub

The problem is that sometimes (not all the time) the application does not print the file. It still move it to the other folder, but it is not send to the printer.
Also sporadically, the printer is very slow in printing the file, by slow I mean sometimes it takes 20 - 40 seconds.

Does anyone see anything that I can fix in the above code? I'm out of options on this and will soon have to try and find another solution, so any help is very much appreciated.

Thanks
-RT

If it is sometimes but not all the times I would think your code is OK, otherwise, it would be causing a problem all the time.

Can you find any consistency in the times when it does not print? Are there high volumes of network traffic during these times? Is the print job actually being sent, but perhaps getting lost in the print queue (the printer you are using is not exactly new/state of the art.)?

Hack- I have not seen any consistency in this problem. Network traffic is not the issue. The third party app, which actually sends the queue, might be the cause of the problem.

Is there any way that I can send the print job out of vb without using the third party app. The reason I chose to use the third party app is that I cannot send it in graphical mode, it needs to be in text mode. If I can do this with pure vb and cut out the other app then I think that would solve some of my problem, it would at least eliminate that from the list of things that could be causing my problem?

Try using ShellExecute to print it and see what happens.

Something like

Code:

---

Private Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" _
(ByVal hwnd As Long, _
ByVal lpOperation As String, _
ByVal lpFile As String, _
ByVal lpParameters As String, _
ByVal lpDirectory As String, _
ByVal nShowCmd As Long) As Long

Private Const SW_HIDE As Long = 0
Private Const SW_SHOWNORMAL As Long = 1

Private Sub Command1_Click()
ShellExecute Me.hwnd, "print", "c:\invprnt\" & TNum & ".txt", , "C:\", SW_SHOWNORMAL 
End Sub

---

is the oki installed on the network, with a tcp/ip address or just as a shared printer installed on a local computer
if it is on a pc any printing has to be done in turn with other stuff running on the host pc, as well as fitting in with network traffic

is your code running on the pc with the printer attached?
are you running your app on each pc, monitoring a local folder?

Quote:

---

Originally Posted by westconn1

is the oki installed on the network, with a tcp/ip address or just as a shared printer installed on a local computer
if it is on a pc any printing has to be done in turn with other stuff running on the host pc, as well as fitting in with network traffic

is your code running on the pc with the printer attached?
are you running your app on each pc, monitoring a local folder?

---

The Oki is installed on a PC and shared, it does not have an ip addy of it's own.
Yes, my code is running on the PC with the printer attached, as well as, the POS app mentioned in the OP.
Yes, each PC has my app running on it monitoring a local folder.

Quote:

---

Originally Posted by Hack

Try using ShellExecute to print it and see what happens.

---

I will give that a try tomorrow and post back, I had an unexpected company road trip today and ran out of time.

-RT

I have a lot of experience debugging problems like this.

First of all, the longer print times are most likely due to the printer occasionally needing to warm up. The printer at my old office used to stay warmed up for 30 minutes which if it received no other printing assignments during that time, it would shut down, and subsequent printing assignments would take much longer, just as you described.

Also, I noticed in your code that you are sending the document to the print queue on the line before you delete it. When a document is sent to the print queue it begins storing an image of the file in the printer's buffer. If the buffer is not able to be completed (like because the file is deleted too quickly), most printers automatically cancel the job.

How to confirm:
You should be noticing that much larger documents are less likely to actually get printed. Try adding a DoEvents between the printing and file moving statements, and you should notice the size of files that usually get printed will be noticeably larger.

I would add the code Hack suggested, followed by a considerable delay (at least 10 seconds) before moving the files. I'm not aware of a way to confirm your printer has finished buffering, but you can add enough of a delay that it becomes irrelevant.

Enjoy. :)

Quote:

---

First of all, the longer print times are most likely due to the printer occasionally needing to warm up

---

it is a oki dot matrix

Quote:

---

Yes, each PC has my app running on it monitoring a local folder.

---

might be better to run your program only on the pc with the printer and to monitor the folders on the other computers as well as the folder on the local pc, or move the files over the network to that pc, then monitor there

Hack - while ShellExecute does print it will not work for me, at lease not as is. The file that is being generated is from a program that was written for DOS and in the text/print file that is generated is the special characters that control the printer. This is why I need text mode rather that graphical. If I print using ShellExecute it prints all of the control characters (boxes, W0, P, F, etc...)
This is why I decided to use the third party app, it interprets the control characters prints accordingly.

deathfxu - all of the files are relatively small and the same size. Also, as stated by west, I am using a dot matrix printer and they don't have a fuser and don't need to warm up.

westconn1 - monitoring remote folders or moving the files to a central loc. is not a very good option for the current setup of the network. I tend to agree with you though, it would eliminate one more thing. but none the less, in the company for which I work this solution is nothing more than wishful thinking and pipe dreams.

If it helps any, the following is the output from the POS, this is what gets sent to the printer. This in not what it looks like when actually printed. The ~~~ are placed by me

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

PE

1107 Highway 49

Marvell, Arkansas 78766

501-829-2786

M


Look Up Account Date: 5/28/08 9:05AM

Inv : W1667821 W0

Cust: W100000W0

By : RT

PF

Stock No. Qty. UM Description Price Extended


123 1 EA PUSH-PULL SWITCH 5.990 5.99

1 1 EA 1 BATTERY 48.990 48.99

CAN 1 EA CAN 0.560 0.56 G

CAN99 1 EA BOTTLE 1.250 1.25 G

CAN12 1 EA 12pk CANS 6.380 6.38 G

BAR 1 EA BAR 0.750 0.75 G

BAR69 1 EA BAR 0.690 0.69 G

BAR99 1 EA BAR 0.990 0.99 G

789 1 EA WILRICH V BOLT 8.870 8.87

987 1 EA WOMEN'S DEERSKIN GLOVES 23.290 23.29

---------

Groc. Tax . . 0.53 Groc. Total . . 10.62

Sales Tax . . 6.97 Merchandise . . 87.14

TOTAL . . W1 105.26 W0 **












Authorized Signature:(X)___________________________________________





Thank you for shopping at Discount Ag Center!!





~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Ok, I think I'm getting close to eliminating the third party app.

This site ( http://support.microsoft.com/kb/q154078/ ) Gives the API to print RAW data to the printer. This is what I need to do, but I suck at getting API's to work for me. So, any help on what exactly I need to change up to get it to work.

-RT

unfortunately i can not test any of this as my dot matrix printers are well gone, but you should be able to send the file to the printer as text, the printer will see the control characters and treat them as such

I have the app working with the info in the link in my prev. post.

It is now running on the PC's at my location for testing, if all runs well for about 2 weeks then I export to other locations, if not then I'm back to square1.