Using MSCOMM 6.0 with Visual C++ 6.0 seems to be working fine. I wrote a test app that shows the packets coming in once a second. Its =20 working much better than the .NET - MSCommLib.MSCommClass code. It stopped once =20 in the last 15 minutes, instead of stopping from 0 to a few seconds every time it = =20 was "kick started" by reading the input with the Input property. So now I get to interface the VC++ 6.0 code to the .NET world. I suppose it will be a DLL, or maybe a helper app with possibly using =20 pipes. I may have to do an independent helper app because C# .NET may interfere =20 with the ability of the VC++ 6.0 code to work properly. Or getting events from = =20 the non-managed DLL to the .NET may be too difficult. A lot depends on how stubborn C# .NET is in getting it to do what I want =20 it to do. Ideas are welcome. Thank you. Dena Meier --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .