PCSGU250 VB2010express Stack Overflow when using CHART & DLL

Instruments PC Oscilloscopes and Recorders
1

PCSGU250 DLL
An application is being developed using VB 2010 express On Windows 7 and Windows XP.
The base for the program is the Velleman Demo VB code.
The VB program is nearly complete and running fine… that is until a “chart” was added.
A button was added to the Demo VB code to open a “chart”.
The code is being run in the debug mode.
The following have been observed:
If any DLL function has been run, the next operation with the “chart” causes this error message:
“An unhandled exception of the type ‘System.StackoverflowException’ occurred in Systems.Windows.Forms.dll”

If the scope is opened from a desktop Icon, there is no error using the chart. It is only after the use of a dll function the above error occurs. That means any button in the Demo that operates the scope, followed by the button to the chart.

Is there some housekeeping needed with the use of the dlls? Or the use of private vs public?
Using a “picturebox” works fine in place of the “chart”. With the chart removed, there are no error messages debugging the code.

First time using VB2010.

2

This strange ‘conflict’ with the chart control seems to occur only with the original PCSGU250.DLL version.
Here is the link to download updated DLL version 1.0.0.1: box.com/s/klgm1mb4cok2jze3y8xl
The only difference compared to the original one is that this new version is compiled with newer Delphi version.
Please replace the old DLL with this new one in the demo project’s folder: \PCSGU250DLL_DemoVB_2010\bin\x86\Debug
Also replace the old DLL in the folders System32 and SysWOW64 if there and everywhere where copied.

3

Thanks. I will update the dll.