profibus help

[CEDEng 0]

Feel free to direct me to a more appropriate forum...this one seemed right! I have some experience with Profibus (and the rest) but it's been a few years. Now I have a requirement I cannot solve on my own, so far. Can I truly simulate a profibus master on my PC, with just the rs232/profi converter? (looks like a 232/485 converter...). I have one of those "master simulator" programs - and it seems to sort of work - but I have also read on many sites and forums that the only way to do it "right" is through hardware (the profibus card for my pc). So - what's the scoop? Can I truly simulate Profibus entirely with software? Is this simulation thing limited somehow? I figure if the code in the simulator can do it - I can write my own code to do it, albeit with pain. I just need to know if it is, in theory, possible, or not? Thanks, all, in advance.