Reverse engineering a QuickBASIC 3.0 program

I have a program (I own the rights) written in QuickBASIC 3.0, though I do not have anymore the source code. Anyone know a decomp开发者_开发问答iler that I can use to see what the program does?

Basically it gets some numbers in input and it performs some calculation, showing some results. Nothing too complicated.

Thanks

I haven't seen any publicly available tools but there's a page from a guy who claims to have made one. You could try contacting him.

I wouldn't recommend trying it on your own if you don't have any experience in reversing DOS programs. It seems QuickBASIC 3.0 was compiled into some kind of p-code. I've never seen any research on the DOS-era p-code, but it might bear some relation to the one eventually used in Visual Basic 6.0, and that one has been investigated quite a lot.

If you vaguely remember the idea but don't remember the details (e.g. actual values of coefficients in the formula), one thing you could try is to enter some numbers, read the results, and save them in an Excel sheet. Repeat that a couple of times and try to plot the data. Not much, but might help.

Use the debugger of Borland C++ 3.1, but you are going to need knowledge of assembler...