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nat_wheatley
08-24-2010, 05:10 PM
I get this fairly often when I 'Write File to SB". Anyone know what would cause it?

Generally when I try to write the file again, it works, but not clear what causes the error.

dana_swift
08-24-2010, 05:24 PM
Nat, what program are you running when you get the error? That is a very odd error indeed.

I am assuming that this occurs when you write your toolpaths from a CAM program for the bot to use. If so, they need to know about this, it is almost certainly a serious bug in their software. It is possible there is something in the post processor that you are using that causes this, in order for that to be the case you would have to be using some very sophisticated software.

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Just what is a stack overflow? Well- first: "what is the stack?".

The stack is a data structure that all software is built around. Conceptually its like a stack of dinner plates in the cafeteria, and overflow occurs when the pile gets too deep. So what does the stack do?

When a program starts, it usually calls other programs to do parts of its work, then when the sub-program finishes the computer goes back and continues from where it left off in the original program. In order to do that, it saves the state of what it was doing on the "stack". When the sub-program completes it removes its information from the stack and goes back to work.

When a program uses variables, they are also stored on the stack. They go away when the program quits and cleanup is automatic.

Almost always a stack overflow occurs when a program calls itself as a subprogram, and gets lost when pushing its information onto the stack. (The process of a program calling itself is called recursion.) It repeats itself without end and in a matter of a few hundred or thousand attempts eventually uses up all the space available to the stack.

There should be nothing you can do to cause this. Its a serious "boo boo" in the code. Let the vendor know as much as possible about what you are doing to get this.

Very complex toolpaths should not cause this.

Hope that helped explain things a little bit-

D