.dll and status bar

[whatsthis 163]

Don't you want to check the status more than once? It looks like you'll only check the status once at the moment. If you put the getStatus call in a while loop, looping while counter < 100, does it change anything?

[Newguy100]

C Code:

//////////////////////////////////////////////////////////////////////////////

int OnDeviceProgram(void){
DWORD iBytesWritten;
DWORD iBytesRead;

count = 0;

while (curr->next) {                         // Move thru whole prepared package link list
          curr=curr->next;

          something = WriteFile(hCom,pData,134,&iBytesWritten,NULL);

          do {

    (ReadFile(hCom,&ch,sizeof(ch),&iBytesRead,NULL));// Wait for receiving
    ch[1]= '\0';

          }while (ch[0]!=ACKNOWLEDGE);              // Wait for acknowledge character
        count = count + 1;                                        //global increments
     }

  return 1;
}

////////////////////////////////////////////////////////////////////////////////////

_declspec(dllexport) int Status(void){
 return count;
}

[Chaos]

Nice, getting closer...

The way its written now the while loop will take almost no time to complete because it can make 100 calls very very fast.  You need a wait in the loop.  Also 100 might not be enough.  You cant use a constant here as different runs will take different amounts to complete.  Instead of a constant 100 iterations replace it with another function call.

In your main loop of OnDeviceProgram() first iterate completely through the list once to see how long it is IE:

max=0;

while (curr->next) {                         // Move thru whole prepared package link list
          curr=curr->next;

          max=max+1;

}

Use this as the stopping point for the while loop and reconfigure it as picture:

(of course you will also then need a "getmaxvalue" function or something).  And I did not change the picture to reflect the new external call...

Message Edited by Chaos on 08-23-2005 02:21 PM

[whatsthis 163]

The code that labview runs to see the status is only run once. Labview needs to start the download and asynchronously execute a function that returns the status of the download multiple times until count == 100. If the dll does this, labview still only sees it once, which will not give you the effect of a status bar.

[Newguy100]

Genius, pure genuis. Thanks a lot chaos and whatsthis, your ideas and assistance pushed me in the right direction. Now my status bar works.

Message Edited by Newguy100 on 08-23-2005 03:02 PM

[Newguy100]

I am using a status bar again to dump a large file up to almost 300000 bytes. (Required). I used the same status bar method as before but this time it only does it once. Here is an attachment. They are nearly identical. I used the same C function. Can anybody explain the difference.

[EVS]

DLL:

Global: FileSize, Current;

Download (filename)

{

           FileSize=GetFileSize(filename);

           do {

           } while (! all downloaded)

}

[EVS]

prev. message is not complete. My baby plays with my notebook 🙂

I developed the status bar like here (pseudocode). VI code looks like yours.

DLL:

// Global

static long filesize, current;
static unsigned char data[MAXBYTES];
static int break_flag

Download (filename)
{
         filesize <- GetFileSize (filename);
         GetDataFromFile (filename, data);

         current=0; break_flag=0;
         do {
              errorcode=download_to_device (data[], numbytes))
              current+=numbytes;
/* Get a chance to other processes  (if it is possible) */
              ProcessSystemEvents();
         } while (download not complete && ! break_flag && !errorcode);

         return errorcode;
}

int GetStatus()
{
    return current / filesize * 100%;
}

void ControlDownload (int flag)
{
    break_flag=flag;
}

Message Edited by EVS on 08-27-2005 03:03 AM

[Newguy100]

I was able to get my status bar working along with my download function, but the thing is that in Labview ver. 6.1, it doesn't react the same way as it is in version 7.1. In 7.1, the status bar actually moves to help me see that the dowload is in progress, but in version 6.1 it remains stationary until the end of the download. How do I make it work like version 7.1.

Message Edited by Newguy100 on 09-02-2005 03:05 PM

[Newguy100]

Are there any other alternatives?