Runtime error 6 - overflow

[rhfurniture]

Hi, I have a file that contains about 128 sequential small CG movements that throws up this error.
It throws out the shopbot program, and when restarted, the position is out in that it says it is at the position before the last command (J2,355.91,718.07)
Has anyone had this problem, and is there a limit to the number of CG commands shopbot can swallow at once?
Or maybe it is just one of them strange things...
I have got round it by simplifying the geometry, thus reducing the number of CG commands in a row - it works ok now. But if there is a limit I would like to know.

Thanks,

R.

[dvanr]

I suspect your limited by the amount of memory you have available.

Something similar happens to me when I tried calculating a spiral. If too many points were plotted it would crash SB3 with a stack overflow or the program would blink out.

[rhfurniture]

Dick,
My computer that runs shopbot has 512 and does not much else, so I doubt it was there (it wasn't a very large part file, just 145 lines of which 128 were CG commands) I havn'nt a clue, but suspect it is some buffer inside the control box, with cg creating large numbers of step/direction signals (or whatever it does).
The reason I want to get to the bottom of this is that I am writing an autocad script that converts splines into multi-arcs and then writes them out as sbp cg commands, and if there is a limit I can put some sort of number check on them.
I guess it probably isn't as simple as that, but some information here would be most useful (it could even go in as part of the PROGRAMMING MANUAL, alongside a list of error codes and their likely causes - Bill please take note....)

R.

[dvanr]

I get mine to crash just be using the preview function and where it crashed varied on the computer, the SB control comp did the worst as it had the smallest amount of memory.

edited

OK I monitored the memory for my program and the program memory seems unaffected. The runtime error is 28 out of stack space.

Best bet is to email Bill and let him run it at the lab.

[rhfurniture]

Interesting. I've run the file on preview on the control computer (first time I'vr run in preview on that one).
1. The memory use never peaks beyond 254
2. This time the error message is more explicit and points to line 74 of the file:

CG,,383.81,389.13,-805583.58,-12960.69,T,1.00,0,1,1,1,0,1,0

This is the first time that a number as big as -805583.58 appears in the part file (the previous max was 68928.55). The number is the X pos of the arc center. Maybe the problem is that the number is over 32k - could this be a limit?

R.

[rhfurniture]

Thinking about it it would probably be sensible to limit the size of arc anyway, so if the spline has a straight part, we don't end up with its centre beyond the beginning of the universe.

(-:

R.

[rhfurniture]

Of course, if working in mm, a limit of 32,000 aka 32meters puts a serious limit on the geometry (eg center distance) ability of our dearly beloved shopbot. Say you were machining arced roof trusses?

R.

[gerald_d]

The boatbuilders often look for arcs of over a kilometer. Using the DOS version we get the kilometer+ arcs and I think the limit there is about 5km(?), but the Windows version may be more restrictive. (We had this exact problem with SheetCam only last week, and the developer posted a fix on Friday).

[rhfurniture]

If this is a limit, then it is the control software that is imposing it. As the CP & CC commands both need figures for center pos or diameter, that only leaves CA , which would not be easy to write to.
Gerald, you couldn't have a look at your files from Sheetcam and see what the arcs are output as and what the largest numbers are?
Even If using Inch units, 32k would limit arcs to 800 odd meters rad.

thanks, R

[rhfurniture]

OK. It's lunchtime.
Playing with part wizard, an arc of 90000mm or less gives a file using the CG command. A file of 99999mm gives a file that uses only M3 commands. I assume that that is the solution from the lads at Delcam have used, so it will have to do me.
That puts the maximum radius for circular interpolation in metric at 90m.
Any finer figure, or technical software limit from shopbot would be most welcome.
Bill, this would be a useful bit of information to put in the new PROGRAMMING MANUAL.

R.